IS136 Layer 3 Messages ViewIS136 Layer 3 Messages View

To open the IS136 Layer 3 Messages view, select it from the View menu. This view displays the Common Air Interface messages as they occur.

Note: In order to log Layer 3 messages, they must be enabled on the Enable Mask tab in the IS 136 Properties dialog, and the Primitives check box must also be checked on the Param Mask tab. To display messages in this view, they must also be selected in the Properties dialog box for this view. For information about the Properties dialog box, click the link below.

The following buttons appear at the top of the view.

Pause / Resume: Click this button to halt the display of new messages. (The button title changes to Resume.) Individual messages can be decoded by clicking the plus box next to the message. While the view is paused, click Resume to start displaying new messages again.

Level 1: While the view is paused, click this button to return to the undecoded message view. (This is the default when the view is first paused.)

Level 3: While the view is paused, click this button to decoded all of the messages that are displayed.

Properties: Click this button to display the Properties dialog box. Select a channel, then select only the messages that you want to view.

About the Over Range

Some E6474A Views allow the Agilent receiver to tune to frequencies over (or under) that which the receiver is specified to cover. Click the link below for details about this added "over range

Layer

Definition 1

A logical block in the communication system. There are seven layers in the ISO/OSI model.

Layer 1

Physical

Layer 2

Data Link

Layer 3

Network

Layer 4

Transport

Layer 5

Presentation

Layer 6

Session

Layer 7

Application

Definition 2

In the Indoor application, MapX allows the user to add detailed geo set data as layers. Adding layers to a map increases the map detail, removing layers reduces the map's complexity (detail).

Layer 3 MessageAlso known as Common Air Interface (CAI) messages, Layer 3 messages report the time, channel (Access, Paging, Sync, Forward or Reverse), and message type. This value is typically reported as a hexadecimal data string.

GSM Layer 3 View

This view displays the Layer 3 messages as they occur. To display this view, click its name under the View menu. Messages can be decoded while a test is running or being played back, after you click the Pause button. To select messages to be displayed, see Properties below.

The following buttons appear at the top of the view.

Pause / Resume: Click this button to halt the display of new messages. (The button caption changes to Resume.) Individual messages can be decoded by clicking the plus box next to the message. While the view is paused, click Resume to start displaying new messages again.

Level 1: While the view is paused, click this button to return to the undecoded message view. (This is the default when the view is first paused.)

Level 3: While the view is paused, click this button to decode all of the messages that are displayed.

Properties: Click the button to display the Properties dialog box. Select a channel, then select only the messages that you want to view.

Examples of message channels are: Broadcast Call Control, Call Control, Call-Independent Supplementary Services, GPRS Mobility Management, GPRS Session Management, Group Call Control, Mobility Management, PDSS1, PDSS2, Radio Resource, and Short Message Service.

For complete information about the Properties dialog box, click the GSM Layer 3 Messages View Properties link below.

Configuration

The System Information (1 thru 8) and Paging check boxes on the GSM Primitives tab in the GSM Properties dialog box must be checked in order to log and display the messages in this view

About The Over Range

Some E6474A Views allow the Agilent receiver to tune to frequencies over (or under) that which the receiver is specified to cover. This added "over range", which usually amounts to approximately 5MHz added to both the high and low ends of each link, was not designed to meet the measurement sensitivity specifications of the receiver. The frequency-to-channel conversion capability of the software is still allowed to function as normal, even though no valid channels actually exist in this range. These non-valid channels provide a sense of how far (in terms of channel spacing) measurements are being made outside of the specified frequency range.

Properties - GSM Layer 3 View

The Properties dialog box allows you to control which messages are displayed in the GSM Layer 3 view. You can also change the text font and color-code the message types. To open it, click the Properties button in the GSM Layer 3 Messages view.

This dialog box also enables pop-up views or "message boxes" that display all of the messages of one type. For more information, see the Notify Section below.

Note: The selections in this dialog box do not affect the settings on the GSM Primitives tab of the GSM Properties dialog box. However, System Information (1 thru 8) and Paging messages must be enabled on the GSM Primitives tab and in this Properties dialog box in order to display them in the GSM Layer 3 view.

Filter TabMessage Groups Section

The section contains the following channels: Broadcast Call Control, Call Control, Call-Independent Supplementary Services, GPRS Mobility Management, GPRS Session Management, Group Call Control, Mobility Management, PDSS1, PDSS2, Radio Resource, and Short Message Service.

Messages Section

This section contains the messages pertaining to the channel highlighted in the Message Groups section above. Messages selected in this section can be added to the Filter In section and the Notify section as described below. Message types are moved to and from this section.

Filter In Section

This section lists the messages that you will display in the GSM Layer 3 view. All message types are included in this section by default.

To remove a message (i.e. filter it out): Select the message in the Filter In section, then click the < (left-arrow) button in the upper group. To remove all of the messages from the Filter In section, click the (right-arrow) button in the upper group. To add all of the messages to the Filter In section, click the >> (double right-arrow) button.

Notify Section

You can display up to five Layer 3 message types in separate pop-up views (message boxes) as they occur. The total number of message boxes enabled is indicated below the Notify section.

To enable a message box view: Select (highlight) the message in the Messages section (or hold down the Ctrl key while you select multiple messages), then click the > (right-arrow) button in the lower group.

To disable a message box view: Select the message in the Notify section, then click the < (left-arrow) button in the lower group. To remove all of the messages from the Notify section, click the 30K data throughput.

RLC UPlink (TBF ON State)

Lists the uplink count of the throughput values at min, max, average, and percentage count for 0K and >30K data throughput.

Reliability Performance Summary

RLC BLER

Displays the RLC BLER found that meets min, max, and average values. Also displays the percentage count at 0% and >20%.

RLC Downlink Retransmission

Displays the RLC downlink retry rate found that meets min, max, and average values. Also displays the percentage count at 0% and >20%.

RLC Uplink Retransmission

Displays the RLC uplink retry rate found that meets min, max, and average values. Also displays the percentage count at 0% and >20%.

RF Performance

RxLev (Full)

Displays the Min, Max, Average and % values of RxLev (Full) that are less than the threshold value set for RxLev.

C-Value

Displays the Min, Max, Average and % values of C-Value that are less than the threshold value set for C-Value.

Overall Performance Summary

This section of the report provides similar information found in the executive summary section. However these tables have additional information and parameters. The parameters provided in this part of the report are:

Table

Parameters provided

Connection Summary

Attach requests

Attach accepts

Attach completions

Attach success rate

PDP context requests

PDP context accepts

PDP context activation success rate

GPRS Attach Duration

Min, Max, Average

PDP Context Activation Duration

Min, Max, Average

Mobility Statistics

Location update requests

Location update accept

Location update success rate (%)

Routing area update requests

Routing area update accepts

Routing area update success rate (%)

GMM Session State

Idle (%)

Ready (%)

Standby (%)

GMM Attach Session

Attach (%)

Detach (%)

TBF Activity

Downlink - Open, Closed %

Uplink - Open, Closed %

Percentage Coding Scheme Utilization

Downlink - CS1, CS2, CS3, CS4

Uplink - CS1, CS2, CS3, CS4

Percentage Time Slot Utilization

Downlink timeslot allocation 0, 1, 2, 3, 4

Uplink timeslot allocation 0, 1, 2, 3, 4

TFI Assignment

Downlink min, max

Uplink min, max

RLC Mode

Ack

UnAck

RLC Uplink Allocation Mode

Single block

Dynamic

Fixed

No Allocation

Data Transfer Summary

RLC blocks received

LLC frames received

RLC blocks transmitted

LLC frames transmitted

RLC blocks/LLC frames

Receive/Send ratio on RLC and LLC

Throughput Performance Summary

RLC Downlink when TBF is open or closed - Min, Max, Average, =0K, and >30K

RLC Downlink when TBF is open - Min, Max, Average, =0K, and >30K

RLC Uplink when TBF is open or closed - Min, Max, Average, =0K, and >30K

RLC Uplink when TBF is open - Min, Max, Average, =0K, and >30K

LLC Downlink when TBF is open or closed - Min, Max, Average, =0K, and >30K

LLC Downlink when TBF is open - Min, Max, Average, =0K, and >30K

LLC Uplink when TBF is open or closed - Min, Max, Average, =0K, and >30K

LLC Uplink when TBF is open - Min, Max, Average, =0K, and >30K

Reliability Performance Summary

RLC BLER - Min, Max, Average, =0%, and >20%

RLC Downlink Retransmission rate - Min, Max, Average, =0%, and >20%

RLC Uplink Retransmission rate - Min, Max, Average, =0%, and >20%

LLC Downlink Retransmission rate - Min, Max, Average, =0%, and >20%

LLC Uplink Retransmission rate - Min, Max, Average, =0%, and >20%

RF Performance Summary

RxLev (Full) - Min, Max, Average, %, and Threshold limit

C-Value - Min, Max, Average, %, and Threshold limit

Signal variance - Min, Max, Average, %, and Threshold limit

RxQual - Min, Max, Average, %, and Threshold limit

MS output power - Min, Max, Average, %, and Threshold limit

Cell Reselection Interval

Min, Max, Average, Total Reselections

Throughput Analysis

This part of the report provides a series of bar-charts and scatter diagrams that graphically display the data given in the previous sections.

The charts include tabular data, cumulative and probability distribution functions (CDF and PDF). All charts have binned values based on the thresholds set for the report. The charts provided are:

RLC downlink throughput

RLC uplink throughput

LLC downlink throughout

LLC uplink throughput

The second part of this section provides information about throughput and what parameters effect it's performance. These include:

RLC downlink throughput versus TBF activity

RLC downlink throughput versus Cell Reselection

RLC downlink throughput versus downlink coding scheme and downlink timeslots allocated

Coding scheme to RLC throughput relation

Timeslots allocated to RLC downlink throughput relation

RLC downlink retry and downlink BLER

RLC downlink throughput, BLER and retry rate

GSM TRAI Reports

This report translates a standard E6474A GSM drive test export (CSV) file and converts it into a format that complies to Telecom Regulatory Authority of India (Microsoft Word or HTML format).

http://www.trai.gov.in/

To generate the required reports:

1. Select GSM > GSM TRAI reports

2. Select Import Date File.

This displays the following dialog box. This dialog box lets you specify report parameters.

The options are:

Group Access Delay - MOC

Group Access Delay - MTC Normal

Group Access Delay - MTC Non Reachable

Call Drop Rate

Voice Quality - Outdoor - Periphery of the city

Voice Quality - Outdoor - Congested area

Voice Quality - Outdoor - Across the city

Voice Quality - Indoor - Office complex

Voice Quality - Indoor - Shopping complex

Voice Quality - Indoor - Other

The following gives a brief description of each component from a typical GSM phone report.

Group Access Delay (MOC)

This part of the report is a summation of the following parts of a normal call procedure.

Time to connect calls - This is the time below "service request" (pressing the send button) and "alerting" (getting the ring-back tone).

Time to confirm instruction to connect - This is the time between "call set-up" (initiating the call set-up command) and "call proceeding" (acknowledged to user).

Time to release call - This is the time between "disconnect request" (pressing the call end button) and "release complete" (being passed on to the network).

Time to alert a mobile - This is measured as a mean of two measurements:

First paging attempt = This is the time between receiving a call request at PLMN and alerting the mobile.

Final paging attempt = This is the time between receiving a call request at PLMN and hearing of the "not reachable" announcement.

Note: It is recommended that you perform at least 10 calls per week, during your busiest network period from your mobile to the drive test system. All tests should be spread across all zones of your network during the course of a quarter.

The Document and HTML formatted reported contains the following information:

Call Number - a unique ID number

Date

Location called from - estimated text value based on RxLev values

Layer 3 Message Diagnostics:

Time of service request

Time of call set-up

Time of call proceeding

Time of Alerting

Time of disconnect request

Time of call release

Time to connect call

Time to confirm instruction to connect

Time to release a call

Group Access Delay (MTC)

This report requires you to enter two parts.

PSTN to Mobile to Call

This dialog box lets you enter data parameters that are added to the database when you select Update.

Select Save to open a saving dialog box. The saved file is auto-imported into analysis reporter and shown with other imported data files.

The second part requires you to import a standard GSM drive test data file.

Call Drop Rate

This report requires you to enter two parts.

Call Drop Rate

This dialog box lets you enter data parameters that are added to the database when you select Update.

Select Save to open a saving dialog box. The saved file is auto-imported into analysis reporter and shown with other imported data files.

The second part requires you to import a standard GSM drive test data file.

Voice Quality

For valid voice quality reports you must follow these guidleines:

RxQual samples are to be collected during time consistent busy hour (TCBH) for the quarter using standard drive test equipment. (Note: measurements using an engineering handset are not acceptable).

It is recommended that at least one drive test be conducted every week during the busy hour, in each of the five location types (Outdoor - Periphery of city, congested area, across the city; Indoor - Office and Shopping complex).

The generated report will have the following format:

Route details

Types of Route

Total no. of sample calls

Number of sample calls with voice quality(in RxQual values)

0

1

2

3

4

Outdoor (Periphery of the city)

Outdoor (Congested area)

Outdoor (Across the city)

Indoor (Office Complex)

Indoor (Shopping Complex)

ALL

Drive Test Results

For valid drive test results, the following guidelines should be followed:

Drive tests should be conducted on at least five routes in each city. This should be made up from three outdoor and two indoor tests.

Each report should be accompanied by coverage maps including color codes for coverage signal strength and voice quality.

Also include hard-copy (print-outs) of any supporting documents for any other results obtained from the drive test.

The output report table has the following layout:

Outdoor Routes

Indoor Routes

Periphery of the city

Congested Area

Across the city

Office Comlpex

Shopping Complex

Route details

1. Coverage-signal strength

2. Voice Quality

a. Total RxQual Samples

b. RxQual samples with 0-4 values

c. %age samples with good voice quality = (b/a) x100

d. No. of RxQual samples with value 5 or more (a-b)

e. No. of RxQual samples with value 5 or more due to network coverage

e. No. of RxQual samples with value 5 or more due to interference

3. Call Success Rate

a. Total Call Attempts

b. Total Calls successfully established

c. Call Success rate (%) = (b/a x100)

%age Blocked calls = 100% - GSR

Call Drop Rate

Handover Data - PCS 1900

Mode: Tracking

Handover data and current serving cell signal data are logged whenever a handover or channel reselection is observed. Before and after values for important signal values are logged as well as information on the handover. Handover Data is viewed in the Handover Monitor view. This view shows before handoff and after handoff values, and the change value between the two.

Each handover record contains the following data:

BCCH

BSIC

RxLev

RxQual

Timing Advance

Dist to BTS

Handover form

Handover cause (if available from Layer 3)

BCCHBroadcast Control CHannelA LOGICAL Control channel continuously broadcasting information about the GSM network, its parent cell, and the surrounding cells. Always found on TN (Time Slot Number) 0; supports network to mobile (downlink) communications only). Range is:GSM1 - 124E-GSM1 - 124 and 975 - 1023DCS1800512 - 885PCS1900512 - 810

BSICBase Station Identity CodeRange = 0 - 77 Octal, 0 - 63 Decimal Octal value is composed of Network Color code, Range = 0 - 7 and Base Station Color Code = 0 - 7

RXLEVReceived Signal Strength LevelThe serving signal strength level based on the strengths all of the signal bursts (RXLEV full) or a subset (RXLEV sub) of the signal bursts over a multiframe period. Range = 0 - 63, representing -110 dBm to -47 dBmBRXLEV - RXLEV before handoverARXLEV - RXLEV after handoverRXLEV neighbors - Received Signal Strength Level on neighboring channels

RXQUALReceived signal QualityThe serving signal quality based on the strengths of all of the signal bursts (RXQUAL full) or a subset (RXQUAL sub) of the signal bursts over a multiframe period. Range = 0 - 7BRXQUAL - RXQUAL before handoverARXQUAL - RXQUAL after handover

TAdv (GSM) Timing AdvanceNumber of Bit periods the transmission burst of a GSM test mobile is advanced to compensate for propagation delay. Used to ensure that the transmission burst arrives at the cellsite at the correct time.Range = 0 - 63.

Dist to BTSThe calculated distance to the cellsite based on the Timing Advance Value1 = 555m, 2 = 1110M, 3 = 1665, etc.

Successful handovers: Handover, Assignment, Immediate Assignment, Location Update, Channel Re-Selection, Channel Release, Partial Release or Frequency Redefinition.

Failed handovers: Handover failure, Assignment failure, Immediate Assignment Rejected, Location Update Rejected, Random Access Failure or IMSI Detach

Handover CauseLayer 3 message field, specifies reason for change of channel taking place.

.

GSM Handover Forms and CausesHandover Form messages

Handover

Handover Failure

Assignment

Assignment Failure

Additional Assignment

Immediate Assignment Rejected

Immediate Assignment

Location Update Rejected

Location Update

Random Access Failure

Channel Re-Selection

Frequency Redefinition

Release

Re-establishment

Partial Release

Unknown

Handover Cause Messages

Normal Event

IMIE Not Accepted

Abnormal Release,

UnspecifiedIllegal ME

Abnormal Release, Channel Unacceptable

PLMN Not Allowed

Abnormal Release, Timer Expired

IMSI Unknown in VLR

Abnormal Release, No Activity on the Radio Path

Location Area Not Allowed

Preemptive Release

National Roaming Not Allowed in this Location Area

Handover Impossible, Timing Advance Out Of Range

Network Failure

Channel Mode Unacceptable

Conjestion

Frequence Not Implemented

Service Option Not Supported

Call Already Cleared

Service Option Not Subscribed

Semantically Incorrect Message

Service Option Temporarily Out of Order

Invalid Mandatory Information

Call Cannot Be Identified

Message Type Non-Existent or Not Implemented

Semantically Incorrect Message

Message Type Not Compatible with Protocol State

Invalid Mandatory Information

Conditional IE Error

Information Element Non-Existent or Not Implemented

No Cell Allocation Available

Conditional IE Error

Protocol Error Unspecified

Message Not Compatible with the Protocol State

IMSI Unknown in HLR

Protocol error, Unspecified

Illegal MS

Unknown MM Cause

Unknown RR Cause

GSM Channel Change Monitor View

To display this view, click its name under the View menu.

This view displays the signal parameters before and after a handover . The handover Form and Cause, Traffic Channels 1 and 2, Power Class, and the BCCH for neighbors 1 through 6 are displayed, in addition to many of the same parameters that appear in the GSM Signal view.

Handoff1) The process by which a cellular mobile is able to move through a coverage area, handing off from cell to cell in order to maintain a good signal quality. The handoff is, ideally, not noticeable to the user. 2) The location at which a call was passed from one cell site to another.

Note: The Motorola T720 phone does not support data in this view. If this view is opened for this phone, no data is displayed.

Form

Cause

LAC

C1

C2

BCCH

BSIC

Cell ID

DTX

RxLev (full)

RxQual (full)

Hop

MAIO

HSN

T Slot

T Ch 1

T Ch 2

Tx Power

TA

PWRC

FER

BCCH

Configuration

The Hand Over check box on the Unsolicited Parameters tab of the GSM Properties dialog box must be checked in order to log data for this view.

About the Over Range

Some E6474A Views allow the Agilent receiver to tune to frequencies over (or under) that which the receiver is specified to cover. Click the link below for details about this added "over rangeLACLocation Area CodeThe entire GSM network is subdivided into small groups of cellsites, each having their own unique code to help identify smaller geographic areas. As GSM phones move throughout the network, they can be tracked according to which LAC they were last reported in. This allows for a more efficient use of resources since the network only has to send messages to a small area rather than to the en

C1Mobile calculated uplink quality parameter used in Cell Selection. Only cells with positive C1 values will be considered for selection. The mobile will choose the cell with the highest C1 value. C1 is a Phase 1 GSM feature which is used to select a cellsite to camp on. It is a function of the received signal strength and the power class of the phone.

tire network

C2C2 is a reselection criteria that is a function of C1. C2 is further used, once camped on a cell, to select a new cell onto which to camp. It incorporates hysteresis to avoid bouncing between cells when a mobile is on a cell boundary. This reduces the number of reselections normally created at a cell boundary. Many providers support C1, and some support both C1 and C2.

Cell IdName or numerical value used to uniquely identify each cellsite or every individual antenna within the wireless network. Defined on a per network basis.

MAIOMobile Allocation Indication Offset Specifies starting point for mobile in Frequency hopping sequence

HSNHopping Sequence NumberGSM supports 64 Frequency hopping sequences ( 1 Cyclic and 63 pseudo-random).

Time Slot1) A uniquely defined increment of time or clock period in which data is transferred. Each time slot is defined by its phase position relative to the reference clock (timing) signal. 2) A multiplexing scheme in which the information from a number of individual circuits is transmitted over one circuit by allowing information from each of the individual circuits to be placed on the common circuit at a particular point (time slot) with respect to a reference timing signal.

Traffic ChannelThe channel that carriers the voice signal. T Ch 1 is the primary channel; T Ch 2 is the secondary channel.

Traffic ChannelThe channel that carriers the voice signal. T Ch 1 is the primary channel; T Ch 2 is the secondary channel. TX Power (GSM)The output power level of the mobile or the base station. Typical levels are 2-19 dBm for GSM, and 2-15 dBm for GSM 1800.

TX Power (GSM)The output power level of the mobile or the base station. Typical levels are 2-19 dBm for GSM, and 2-15 dBm for GSM 1800.

FERFrame Erasure RateThe number of corrupted or invalid speech frames per measurement.

Orbitel 907 GSM900 tracking phones report raw FER measurements from 0 to 24, where 0 = 0% frame erasure, 12= 50%, and 24 = 100% for full rate channels.

All Sagem GSM phones report FER as a percentage of 0 to 100%.

MCCMobile Country CodeRange = 0 - 999

MNCMobile Network CodeRange = 0 - 99

DSFDownlink Signaling Failure - Actual DSF counter values between 0 and DSF (Max)DSF Max - Maximum Down Link Signaling Failure - Network defined upper limit of DSF counterDSF is used to determine a downlink signaling failure when the phone is in "idle mode." Every time a CCCH message (Paging Sub-Channel) message is decoded properly, the DSF counter is incremented by two. For every incorrectly decoded message, the DSF counter is decremented by four. If the counter reaches zero, a downlink signaling failure has occurred.

RLTRadio Link Timeout (GSM)Actual counter values between 0 and RLT MaxRLT Max - Maximum Radio Link Timeout - network defined upper limit of RLT counter.RLT is used to determine if a radio link failure occurred in "dedicated mode." Every time a (SACCH) control channel message is decoded properly, the RLT counter Is incremented by two. For every incorrectly decoded message, the RLT counter is decreased by one. If the counter reaches zero, a radio link time out has occurred and the call is dropped.

Frequency Hopping

To average the fading conditions found over a range of channels, the Base Station may use a range of channels over which a call can be maintained. Frequency hopping reduces the signal-to-noise ratio.

Frequency ModulationA form of modulation where a change in the amplitude of the input signal causes a change in the frequency of the carrier signal.

FSKFrequency Shift Keying A form of modulation where the carrier signal is varied between two frequencies (representing 1 and 0) in response to an incoming digital DSP

(Digital Signal Processor) The component in the RF coverage measurement system that makes general RF measurements as well as CDMA & GSM specific measurements.

BERBit Error RateThe number of errors, expressed as a fraction of the total number of bits sent, of a digital signal.

Analog RSSIAnalog Received Signal Strength Indicator

Upper Adjacent ChannelThe signal strength of the upper adjacent channel in call tracking data. The channel with a number one greater than the channel being monitored.

Lower Adjacent ChannelThe signal strength of the lower adjacent channel in call tracking data. Designated as lower with a number one less than the channel being monitored.

GSM Signal View

This view shows the following call tracking parameters. This view is used for GSM 900, 1800, 1900, and Dual Band tracking phones. To display this view, click its name under the View menu.

The following parameters are displayed in this view. For definitions, click "Signal Parameters", below.

Mobile State: This field displays the phone state during a test. The states displayed are:

No Servicephone is not camped on to a network.

Dedicatedphone in a call, camped on to a network.

Idlephone not in a call but camped on to a network.

Serving Cell: This area displays measurement data about the cell that the phone is currently in. The fields in this area are:

Channel

Displays the broadcast channel in use on the serving cell. If you right-click the field label the display will change to show the Cell Name. This name is extracted from the StationInfo.txt file based on GPS and cell information.

BSIC

Indicates the serving cell base station identity code (BSIC).

MCC

Displays the Mobile Country Code.

LAC

Displays the Location Area Code. This value is displayed in decimal units.

Cell ID

Displays a unique hexadecimal number assigned to the serving cell. This value is displayed in decimal units.

MNC

Displays the Mobile Network Code.

Mobile Measurements: This area displays measurement data about the Rf interface. The fields in this area are:

TCH

Displays the unique TCH channel number(s) being used by the phone during a call. When hopping is used during a call, this text box is empty, and all TCH channels display in the Hopping list.

Tx Level

Indicates the power being used for transmission by the phone. This is a value from 0-31.

RxLev (F)

Displays the service signal strength (dBm) measured over a full set of traffic and SACCH frames.

RxLev (S)

Displays the service signal strength (dBm) measured over a sub set of 4 SACCH and 8 SID (Silence Descriptor) frames.

RxQual (F)

Displays the service signal quality. This will be a value from 0-7 measured over a full set of traffic and SACCH frames.

RxQual (S)

Displays the service signal quality. This will be a value from 0-7 measured over a full set of traffic and SACCH frames.

DTX

Displays the discontinuous transmission state. This can be ON or OFF

FER

Frame Erasure Rate. The percentage of lost or bad speech frames. This field is not displayed if frame erasure measurements are not supported by the attached mobile. Sagem phones report FER as a percentage. The range is 0 to 100%.

TA

Displays the timing advance being used during a call. This is given in bit periods and can have a value from 0-63.

TSlot

Displays the timeslot being used by the network during a call. This can be a value from 0-7.

Type of channel

Displays the logical channel type used

DSF

Displays the actual and network assigned downlink signalling flag counter.

RLT

Radio Link Timeout Counter. The initial display being the maximum value as defined by the network. This displays the actual and maximum values.

Avg C/I

Displays the aggregate carrier to interferer (C/I) value for the serving channel. It is calculated from the C/I list using the following method:

Avg C/I = 10 Log ((10 pwr(CI1/10) + 10 pwr(CI2/10) . . . . + 10 pwr(CIn/10))/n)

Frequency Hopping: This area shows all measurement information related to hopping. The fields displayed are:

Hopping: Displays type of hopping used.

MAIO: Displays the Mobile Allocation Index Offset value.

HSN: Displays the Hopping Sequence Number.

Hops: Display number of hops made during a call.

Hopping List: This list contains the available hopping channels for the GSM network. The list is passed from the network to the phone.

Carrier to Interference Hopping List: This area displays lists of data when hopping is detected and decoded.

ARFCN List: A list of ARFCN channels that are detected (Channel Numbers).

RxLev List: A list of received signal strengths (dBm).

C/I List: A list of carrier to interference values (dB).

Note: Some of the parameters listed above must be enabled for collection on the Unsolicited Parameters tab of the Properties dialog before starting a data collection test.

Channel Display Options

Show Channel Number or Cell-site Name: You can choose to display either the channel number or the cell-site name. Right-click on the "Cell" label, then choose Show Name or Show Channel from the pop-up menu. When you choose Show Name, the "Cell" label changes to "Name", and the cell-site name, BCCH, and BSIC are all displayed in the Name field.

Cell-site Name Origin: If you have chosen Show Channel above, right-click within the CN field, then choose Use Channel, Use Channel and Qualifier, or Use Cell Id from the pop-up menu to determine how the Cell-site name is derived.

Description of GSM Measurements

The GSM measurement suite provides complete analysis of the base station downlink broadcast channel. For each broadcast channel (BCH), signal quality and strength are measured.

MeasurementDefinition

BSIC

For each BCH found, the base station identity code can be decoded. This then provides the base station color code (BCC), network color code (NCC), enabling identification of the cell being measured.

Channel Number

A range of frequencies or channel numbers (ARFCN) can be selected for focussed scanning of a particular cell or part of a network.

Burst power measurement

The measurement is synchronized to the BCH and burst power for the GSM timeslot is measured. This is used for determining signal strength for adequate cell coverage. This measurement is carried out when the BSIC is being decoded.

Fast Power Measurement

When the BSIC is not being decoded, fast channel power measurements can be made.

Adjacent Channel Analysis

Measurement of the power of two carrier signals (Carrier A and B) and the power of each of the channels either side of the carrier (C) signals, that is C-1 and C+1.

Co-Channel Analysis

Measurement of a primary signal, multi-path components and other components that are not part of that signal. These components being noise or secondary channels.

ARFCN Absolute Radio Frequency Channel Number(0 to 1023)A numeric code used to represent a frequency channel in GSM or DCS networks. The range is:GSM1 - 124E-GSM1-124 and 975 - 1023DCS1800512 - 885PCS1900512 - 810

BCCHBroadcast Control CHannelA LOGICAL Control channel continuously broadcasting information about the GSM network, its parent cell, and the surrounding cells. Always found on TN (Time Slot Number) 0; supports network to mobile (downlink) communications only). (0 to 1023)Range is:GSM1 - 124E-GSM1 - 124 and 975 - 1023DCS1800512 - 885PCS1900512 - 810

BSICBase Station Identity CodeRange = 0 - 77 Octal, 0 - 63 Decimal Octal value is composed of Network Color code, Range = 0 - 7 and Base Station Color Code = 0 - 7

C1Mobile calculated uplink quality parameter used in Cell Selection. Only cells with positive C1 values will be considered for selection. The mobile will choose the cell with the highest C1 value. C1 is a Phase 1 GSM feature which is used to select a cellsite to camp on. It is a function of the received signal strength and the power class of the phone.

-64 to+64

C2C2 is a reselection criteria that is a function of C1. C2 is further used, once camped on a cell, to select a new cell onto which to camp. It incorporates hysteresis to avoid bouncing between cells when a mobile is on a cell boundary. This reduces the number of reselections normally created at a cell boundary. Many providers support C1, and some support both C1 and C2. -64 to +64.

Carrier PowerThe received power of the current channel derived from the receiver. Similar to Rx Power derived from the tracker. -120 to -20.

Cell IdName or numerical value used to uniquely identify each cellsite or every individual antenna within the wireless network. Defined on a per network basis. 0 to 65535

DSFDownlink Signaling Failure - Actual DSF counter values between 0 and DSF (Max)DSF Max - Maximum Down Link Signaling Failure - Network defined upper limit of DSF counterDSF is used to determine a downlink signaling failure when the phone is in "idle mode." Every time a CCCH message (Paging Sub-Channel) message is decoded properly, the DSF counter is incremented by two. For every incorrectly decoded message, the DSF counter is decremented by four. If the counter reaches zero, a downlink signaling failure has occurred. 0 to 45.

DSF(max)Downlink Signaling Failure - Actual DSF counter values between 0 and DSF (Max)DSF Max - Maximum Down Link Signaling Failure - Network defined upper limit of DSF counterDSF is used to determine a downlink signaling failure when the phone is in "idle mode." Every time a CCCH message (Paging Sub-Channel) message is decoded properly, the DSF counter is incremented by two. For every incorrectly decoded message, the DSF counter is decremented by four. If the counter reaches zero, a downlink signaling failure has occurred.

FERFrame Erasure RateThe number of corrupted or invalid speech frames per measurement.

Orbitel 907 GSM900 tracking phones report raw FER measurements from 0 to 24, where 0 = 0% frame erasure, 12= 50%, and 24 = 100% for full rate channels.

All Sagem GSM phones report FER as a percentage of 0 to 100%.

Hopping FlagIndicates whether frequency Hopping currently enabled on network.(0,1)

Hopping List The list of channels the phone can utilize during a call.

Hopping Sequence Number The pattern that the Absolute Radio Frequency Channel Numbers in the Mobile Allocation Table follow. 0 to 63

LACLocation Area CodeThe entire GSM network is subdivided into small groups of cellsites, each having their own unique code to help identify smaller geographic areas. As GSM phones move throughout the network, they can be tracked according to which LAC they were last reported in. This allows for a more efficient use of resources since the network only has to send messages to a small area rather than to the entire network.(0 to 65535)

Lower Adjacent ChannelThe signal strength of the lower adjacent channel in call tracking data. Designated as lower with a number one less than the channel being monitored.(-120 to-20)

MAIOMobile Allocation Indication Offset Specifies starting point for mobile in Frequency hopping sequence.(0 to 63)

. RLTRadio Link Timeout (GSM)Actual counter values between 0 and RLT MaxRLT Max - Maximum Radio Link Timeout - network defined upper limit of RLT counter.RLT is used to determine if a radio link failure occurred in "dedicated mode." Every time a (SACCH) control channel message is decoded properly, the RLT counter Is incremented by two. For every incorrectly decoded message, the RLT counter is decreased by one. If the counter reaches zero, a radio link time out has occurred and the call is dropped. (0 to 64)

RLT(max)Radio Link Timeout (GSM)Actual counter values between 0 and RLT MaxRLT Max - Maximum Radio Link Timeout - network defined upper limit of RLT counter.RLT is used to determine if a radio link failure occurred in "dedicated mode." Every time a (SACCH) control channel message is decoded properly, the RLT counter Is incremented by two. For every incorrectly decoded message, the RLT counter is decreased by one. If the counter reaches zero, a radio link time out has occurred and the call is dropped.

Time Slot1) A uniquely defined increment of time or clock period in which data is transferred. Each time slot is defined by its phase position relative to the reference clock (timing) signal. 2) A multiplexing scheme in which the information from a number of individual circuits is transmitted over one circuit by allowing information from each of the individual circuits to be placed on the common circuit at a particular point (time slot) with respect to a reference timing signal.(0 to 7)

Timing AdvanceNumber of Bit periods the transmission burst of a GSM test mobile is advanced to compensate for propagation delay. Used to ensure that the transmission burst arrives at the cellsite at the correct time.Range = 0 - 63

TX Power (GSM)The output power level of the mobile or the base station. Typical levels are 2-19 dBm for GSM, and 2-15 dBm for GSM 1800.(2 to 19)

Upper Adjacent ChannelThe signal strength of the upper adjacent channel in call tracking data. The channel with a number one greater than the channel being monitored.(-120 to -20)

BERBit Error RateThe number of errors, expressed as a fraction of the total number of bits sent, of a digital signal.

Band The scanned frequency for which signal strength data is listed in iDEN, GSM, and PDC data collected using a broad-band scanning receiver

Analog RSSIAnalog Received Signal Strength Indicator

Aggregate Power

Aggregate is the measure of the spreading of a signal over time due to multipath and low signal noise. In the process of correlation, as the point of maximum correlation is approached, the power is above the noise. Aggregate power is a measure of the power to either side of the peak and above the noise. If the aggregate power is greater than the peak power, multipath is indicated.

Adjacent Channel

You can make adjacent channel power measurements. This measurement will return the ratios of the power at the carrier frequency and that of the power of a channel either side.

Up to two carriers can be selected and displayed.

The power levels depend on the offset used. One channel offset (200 kHz) means interfering signal is transmitted at a level 9 dB above that of the desired signal, and a two channel offset (400 kHz) means that the signal is transmitted at a level 41 dB above the desired signal.

Blocked CallA call that the cellular network did not assign to a voice or traffic channel within a specified time because of network faults or for lack of available capacity.

L-Band

The portion of the signal spectrum that includes frequencies from 390 MHz to 1550 MHz. The GPS carrier frequencies (1227.6 MHz and 1575.42 MHz) are included in the L-band.

Band:

Band: -1

Band: DCS1800

Band: GSM900

Band: IS-136/850

Band: IS-136/1900

Band: IS95

Band: J-CDMA

Band: J-STD-007

Band: J-STD-008

Band: K-CDMA

This keyword specifies the wireless band to be used for correct proper channel / frequency correlation. The value set by Band is persistent: it will remain in effect until another Band statement is encountered. The initial value for Band is -1 which implies "not specified." If Band is specified AND the phone supplies a Band value, it will be used in conjunction with channel (if specified) to match cell sites.

Statistics Menu

Calls are categorized and counted as follows. Click (to check) next to each call category to show or hide it. A check mark next to the item indicates that it is displayed.

Total - This shows the total number of calls made during the test.

Good calls - This shows the total number of calls for which no problem was observed and the user-defined signal thresholds were not exceeded.

Blocked calls - This shows the total number of calls that the cellular network did not assign to a voice or traffic channel within a specified time because of network faults or for lack of available capacity.

Dropped calls - This shows the total number of calls that ended before expiration of the call duration timer due to signaling or RF problems.

No Service calls - This shows the total number of calls that could not be placed or completed due to the loss of network service.

No Comm This shows the total number of "No Comm" calls. If a call is ended by the software and the phone does not react to the End key command, the next time the software instructs the phone to place a call, it will find it unavailable. The failed attempt is also classified as No Comm. This type of No Comm can occur with E6473A systems. An example of a reason a call is classified as a No Comm is Rx Burst Timeout .

MPIO - My Phone Is Off. This shows the total number of calls made to another phone in the data collection system that were not answered. (The called phone was never assigned a Voice channel.)

Progress - A message indicating the call progress is displayed in this field. Possible messages are: Initializing, Idle, Dialing, Setup, On Call, and Continuous Call. In addition to the messages, count-down values are displayed for Initializing, Idle time, Setup time, and On Call time. The count for each phase starts with the Call Duration, Idle Time, and Call Setup values entered on the Autodialing tab of the phone's Properties dialog box. When a test is started, "Initializing" is displayed, with an initial value of 30.

Setup - This indicates the time period between the time the phone number is dialed and the time the phone is assigned a Voice channel.

Breakdown - This indicates the time period between the time the END key is pressed and the time the phone is assigned a Control channel.

Power Measurements

The system is capable of measuring power using various methods. The following list describes how the techniques used, are calculated and displayed.

Spectrum and CW analyzer

RMS power measurement.

Channel analyzer

Total channel power.

Broadcast channel and adjacent channel analyzer

Power averaged over 8 timeslots.

Broadcast channel with BSIC decoding

Power is measured over 1 timeslot.

Co-channel analyzer

Power of the dominant component measured over 11 frames.

RxLev_Access_Min

Minimum received level at the mobile required for access to the system.

These values are sent on the BCCH by the base station on the layer 3 and 4 messages

Properties - GSM Layer 3 View

The Properties dialog box allows you to control which messages are displayed in the GSM Layer 3 view. You can also change the text font and color-code the message types. To open it, click the Properties button in the GSM Layer 3 Messages view.

This dialog box also enables pop-up views or "message boxes" that display all of the messages of one type. For more information, see the Notify Section below.

Note: The selections in this dialog box do not affect the settings on the GSM Primitives tab of the GSM Properties dialog box. However, System Information (1 thru 8) and Paging messages must be enabled on the GSM Primitives tab and in this Properties dialog box in order to display them in the GSM Layer 3 view.

Filter TabMessage Groups Section

The section contains the following channels: Broadcast Call Control, Call Control, Call-Independent Supplementary Services, GPRS Mobility Management, GPRS Session Management, Group Call Control, Mobility Management, PDSS1, PDSS2, Radio Resource, and Short Message Service.

Messages Section

This section contains the messages pertaining to the channel highlighted in the Message Groups section above. Messages selected in this section can be added to the Filter In section and the Notify section as described below. Message types are moved to and from this section.

Filter In Section

This section lists the messages that you will display in the GSM Layer 3 view. All message types are included in this section by default.

To remove a message (i.e. filter it out): Select the message in the Filter In section, then click the < (left-arrow) button in the upper group. To remove all of the messages from the Filter In section, click the (right-arrow) button in the upper group. To add all of the messages to the Filter In section, click the >> (double right-arrow) button.

Notify Section

You can display up to five Layer 3 message types in separate pop-up views (message boxes) as they occur. The total number of message boxes enabled is indicated below the Notify section.

To enable a message box view: Select (highlight) the message in the Messages section (or hold down the Ctrl key while you select multiple messages), then click the > (right-arrow) button in the lower group.

To disable a message box view: Select the message in the Notify section, then click the < (left-arrow) button in the lower group. To remove all of the messages from the Notify section, click the Options, Other tab.

Threshold

Select to change the number of measurement results displayed. Only the measurements with a result greater than or equal to the threshold value will be displayed. For bar chart displays only.

This may reduce the number of measurement results displayed.

Description

The Interference Analyzer view measures the power of a serving channel and the upper and lower adjacent channels. This function is primarily intended for use in systems with Agilent E6474A option 220. Typically, the carrier frequency of the adjacent channel interference measurement is linked to the serving channel of the phone. When the phone is handed-off to a new channel, the adjacent channel interference measurement tunes to the new channel.

The Interference Analyzer interference measurement can also be used independently from the phone. A user can define a specific channel to measure along with the associated upper and lower adjacent channels.

Adjacent channel interference may arise from other cells/sectors in the network. Two independent adjacent channel interference measurements are provided in a single view. This is intended for two phone configurations. Each adjacent channel interference measurement can be linked to one of the phones.

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Overview of GSM Interference Analyzer View

The Interference Analyzer provides measurements of both Adjacent Channel and Co-Channel interference.

Adjacent channel interference may arise from other channels in the same cell or from neighboring cells.

Co-Channel interference may arise from base stations in neighboring and more distant cells using the same frequency as the current channel. If the network is set up correctly, neighboring cells should not re-use the same channels.

The total signal power at the antenna of a phone can be composed of combinations of the following components:

Direct path signal (primary)

Short multi-path components (short fading)

Long multi-path components

Co-channel components

The direct path signal is defined as the signal arriving from the base station by the most direct path.

Short fading components are signal components that might have reflected from nearby objects and are delayed from the direct path component by less than 1 symbol period.

Long path components are signal components that have reflected from more distant objects such as hills and mountains and are delayed from the direct path component by greater than 1 symbol period. The co-channel component is a signal received from a secondary signal source transmitting on the same frequency as the primary signal. Click here for a diagram.

In an ideal environment there would be no co-channel signal and no multi-path components. In this situation the received signal strength from the primary base station would be constant at a given location and would decrease with distance from the base station.

In typical real life situations this is not the case. Each of the signal components combines to produce a signal that varies over short distances. As a phone moves over even relatively short distances the angle of incidence of the short fading components changes by a greater amount that for long fading components. This results in changing phase and amplitude relationship for each of the components.

The receiver samples 11 frames of the GSM signal. Sampling 11 frames ensures that the sampled data will always contain an FCH/SCH sequence of the GSM BCH. The sample rate is such that the relationship for individual samples is quasi-stationary, however over the 11 frames of sampled data the vehicle will have moved a short distance and the sampled signal will show the characteristics of all contributing signal components. See this diagram for the resultant signal trend.

In order to analyze the received data and make measurements of the signal components we must first find a reference point within the sampled data. This is done using standard techniques to find the FCH/SCH pattern within the sampled data. Having found the FCH/SCH the sampled data is adjusted to correct for carrier and symbol lock. The received data is filtered and peak detected to estimate the trend of the direct path and short fading components.

The key to analysis of the signal components is the constellation pattern produced by GMSK modulated signals such as GSM. Once the sampled data has been symbol locked we are able to analyze the constellation pattern for the middle 48 bits of the SCH mid-amble.

For an ideal signal with only a direct path component it is possible to rotate each point on the constellation such that each point lines up at a single reference position. Rotating the vectors to a reference position in the presence of short fading results on this sort of graph . The direct path vectors align but there is a small variation in the alignment of the short path components due to the change in these components over the period of the 48 symbols. This results in a smear of the short path vector. The path of the resultant vector is the signal trend arising from the direct and short path components.

The co-channel and long path components appear uncorrelated with the primary and short path components and would be shown on the constellation diagram as a constellation around the resultant vector.

This diagram shows the impact of co-channel and long path components on the constellation diagram. In practice the constellation for long-path and co-channel components will describe a circle around the resultant vector due to the rotation applied to each point to align the direct path components.

Long path components are time shifted images of the direct path signal. A correlative modeling technique is used to construct the best fit for the long path components. The Agilent E7475A application uses this data to graphically show the delay spread of long path components. This data can now be removed from the signal data leaving only direct, short and co-channel components.

Short path components can be removed by analyzing the smeared vector component resulting from the short path. Each short path vector is removed by applying an equal amplitude component out of phase by 180 degrees.

The final stage of the analysis is to remove the direct path component. This is done by moving the constellation to the origin. The co-channel signal is now left as a ring around the origin. Applying the reverse rotation to that applied to each point in the earlier stages returns the constellation points to their correct position allowing analysis of the co-channel component.

The GSM Interference Analyzer view presents the following results:

Total Power

Primary Power

Fading (Short path)

Primary/Interferer

Primary BSIC and cell name

Secondary BSIC and cell name

The delay spread results are presented graphically.

All of the above results are logged in the system database along with the geographic location of the measurement. The results can be replayed within the application or can be exported to GIS post-processing software for in-depth geographic analysis.

GSM Phone Reports

The following gives a brief description of each component from a typical GSM phone report.

Executive SummaryCall Statistics Chart and Details

This chart and table shows calculations and statistical analysis of call performance during the drive test. All the calculations are based on GSM Layer3 message analysis (except for Total RF drops).

Total RF Drops refers to number of times the radio link counter's current value reached zero.

Quality Performance Summary

This table is a summary of some critical quality parameters, which are listed showing Min, Max, and Average values for critical quality parameter values.

The table also shows a percentage exceeding-threshold calculations. These thresholds are defined in the thresholds settings.

Certain parameters do not have Min, Max, and Average values. This is because these are textual state values. The hopping parameter shows in average column Hop, which is actually the mode of TCH State.

N1_Rxlev and N2_Rxlev, refers to the first and second strongest neighbor channels Rxlev.

Note: The calculations for greater and less () are not changeable in this current release.

Overall Performance Summary ReportPhone Call State

This chart is a simple Histogram of the three possible phone states reported by the Phone. This chart is useful in getting an idea on what was the phones activity during the drive test. For example if the Phone was Idle for the most of times(example: 98% ), then the RxQual and other Dedicated mode parameters which were reported in the remaining very low (2 %) Dedicated state really does not add much value.

DTX State

This chart shows the uplink DTX state as reported by the phone.

Hopping State

This is a useful chart to be used in correlating the quality parameters with the channel assignment and network configuration.

Hopping is expected to improve the performance of the network, therefore if the Hopping percentages are high, it means that the calls are mostly maintained on Hopping channels. If quality is bad, then either Hopping parameters or RF needs optimisation.

RxQual Sub

This is a histogram chart of RxQual_Sub, the chart shows values over all possible discrete values of RxQual_sub (ranging from 0 to 7). RxQual_sub is a prime indicator of air interface quality of communications.

FER

This chart shows FER.

Very high values could be expected in higher FER bins. This is can be due to the fact that FER is reported by the phone as Full (that is measured over all speech frames). If DTX is in use, and depending on speech coming in , there could be several DTX ON states. This can result in high FER.

If DTX is used in the network, it is recommended not to rely on this parameter, other than for exceptional cases where the information used for testing (like some varying Music) ensured that DTX state is never turned ON.

RxLev Full and RxLev Sub chart

This chart shows both Rxlev_full and Rxlev_Sub.

Rxlev_Sub is used in dedicated mode when the DTX is ON. If DTX is not ON, Rxlev_sub will be same as Rxlev_full.

Rxlev_Full can not be relied upon if DTX ON in dedicated mode. However for Idle mode Rxlev_Full it is a useful parameter for getting coverage indications. During dedicated mode, both Rxlev_Full and Rxlev_Sub are subject to Downlink power control.

Tx Power (dBm)

This chart shows Tx Power, by plotting TxLev (and not absolute power values).

The values along the bottom of the chart indicate higher transmit power. If there are high percentages found, then the phone was transmitting at higher power.

This can result in higher probability of Uplink interference generation for other users, and since the Tx Power levels are controlled by the cell, a higher level of Tx Power also indicates poor uplink quality.

Timing Advance

This chart shows Timing Advance values. Each integer indicates an RF Propagation distance between the phone and the cell as approximately 550m.

As the value gets higher, it indicates that the phone was communicating with the cell from very large distance.

There could be several reasons behind getting higher value percentages:

Cell Dragging

Poor Coverage

Repeater

Cell Overshoot

These problems and their diagnosis can be done, to a certain extent, by using other charts and analysis table in this report.

RLTC Current Values Changes

This is not a cChart of simple RLTC values. It is a histogram of probability of RLTC value changes.

The RLTC counter in GSM controls the RF abnormal release process (Drop calls). RLTC is assigned a max value which is maintained by the phone in dedicated mode. If the phone is not successful in decoding a SACCH block, it decrements the RLTC counter by 1, if it is successful in decoding it increments by 2, but not exceeding the absolute current value greater than the max value.

This chart displays the difference between the RLTC max value and the current value for every reported sample from the phone.

If the difference is 0 then it means the SACCH blocks are getting decoded, as the difference value increase, we know that the current value is decrementing. This indicates the severity in received quality.

In this chart, a large percentage will be expected for 0, similarly to the right of the chart, for values in the range of 10 and above, means that the counter decremented by 10 from its current value. This indicates the consistency in the bad quality.

This type of calculation gives you a very good indication of RF quality severity under varying conditions of RLTC max values.

DSF Current Value Changes

Similar to the RLTC current value changes chart, this chart represents the DSF (Downlink Signalling Failure) parameter, which decrements by 4 and increments by 1 for every unsuccessful and successful decode of paging message in the IDLE Mode.

If the DSF counter changes, this indicates the number of Paging Blocks which were missed by the phone and hence the quality in the Idle Mode. The calculation for this chart is similar to the RLTC current value changes.

Call Quality Analysis ReportRxLev and RxQual variations

This is a snapshot analysis to see the impact of RxLev on quality. You should focus on the chart areas where RxQual is poor, and then see what was the RxLev variations around these poor RxQual areas. This indicates where poor quality is due to interference or coverage issues.

RxQual (Sub) versus RxLev (Sub)

This is an X-Y view of the RxLev and RxQual relationship.

For higher values of RxLev on the x-axis, lower and almost 0 values of RxQual can be expected. For higher values of RxLev, higher RxQual values are seen. This indicates that this network (or this drive area) is prone to interference.

Uplink Performance Estimation

The cell controls the phone transmit power, and this control is based on two parameters:

Uplink Received Signal Level

Uplink Received Signal Quality

Ideally the RF link should be balanced for Gains/Losses and hence any change in the Downlink receive level should effect the same kind of Signal level change in the Uplink.

This means if the Downlink Signal level is good, the Uplink Signal level should also be good and hence if Downlink Quality is good, the Uplink should also be good. This occurs when the Tx Power is low (as per the power control algorithm).

For good signal level, a high amount of Tx Power is seen. This means the Uplink quality is bad despite of good signal level, which means probability of interference.

Therefore this chart correlates the Downlink received level to Uplink transmitted power, indicating the probability of interference in the Uplink. In certain networks, due to improper settings and control at the cells, the phone always starts with high power level transmission after every handover as is commanded to the phone in the handover command message.

Distance to Coverage

This chart shows the relationship between distance and coverage.

Ideally as the distance increases the coverage should proportionately decrease based on terrain data.

However there could be instances where depending on conducting bodies like water, low absorbing reflector, or higher altitudes, you can get good signal lever at larger distances. This helps when we analyze what kind cell balancing is there in the network.

Quality to Handovers (EGSM)

The above three charts for Quality to Handovers are similar. The only difference is that the secondary axis parameter, BCH, is split into three ARFCN bands:

P-GSM

E-GSM

DCS-1800

This is done so that the BCH changes become visible on the chart. If all the BCH values are plotted one chart, and with the ARFCN range from 1 to 1024, scaling becomes an issue.

These charts plot the BCH value against RxQual_Sub. Any change in BCH value indicates a Handover (in dedicated mode) and a Cell Reselection (in Idle Mode).

You can see for Handover points (where BCH changes) and what the RxQual was at that point.

Quality to BCCH (GSM) and (DCS)

These two charts (separated on frequency bands), plot the RxQual for every BCCH. This is helpful to spot whether quality problems, overall, are due to a few bad channels or if it is spread all over.

Quality to BCCH versus BSIC (GSM) and (DCS)

These two charts are again separated by frequency bands. These charts plot the BSIC value v/s BCCH.

In GSM cells re-use is discriminated by BSIC values. Hence BSIC becomes an ideal value for identifying interferers. These charts can be viewed for generic analysis. If you see more than one BSIC for a BCCH, then this could be that the phone moved through multiple co-channel carriers. This could happen if the drive test was long or possibly the BSIC toggled with interfering carriers.

The second use for these charts is when the drive test is done for a specific purpose of troubleshooting an interferer. Where the phone is locked on to a BCH. At that time the phone would start losing out on the prime carrier and might start reporting instances of the interferer BSIC. This is easily spotted from this chart.

Quality versus TCH State

This chart gives a spread of RxQual with respect to the state of traffic channel. Even if the channel was hopping or not. From this you can see which mode of TCH (Hopping or Non-Hopping) is giving poor quality.

Performance By Cells Report

This analysis is a highly detailed drilled down analysis where the entire drive data is filtered for every unique cell which the phone traversed during the drive.

For every cell there is a statistical analysis for critical parameters from which you can easily find out the problem cells. This data helps you in trimming down analysis in post-processing down to selected cells, rather than the total drive.

The last column, for every parameter in the table, provides details on what kind of statistical calculation has been made.

The parameter Availability supercedes other statistical parameters.

If Availability is low then the cell can be ignored or if a particular cell or cells is/are having accessibility or usage problem, you can assess this from this parameter.

Note: If Availability is low, certain parameter statistics might not be applicable since the phone might not have gone through the states to get these measurement parameters.

At the end of the Performance by Cells table, there is a short summary table, which lists the overall performance on a cell basis. The explanation of these parameters is given in an extra column. These parameters help in highlighting how much distribution of poor quality and/or coverage there is over cells.

Note: A very interesting application of the above data is that this data can be taken out in a CSV form and loaded into a Post Processing Table, hence along with the full drive data, we can see a layer of cell summary, giving us complete guidance on our data analysis approach

Performance By Calls Report

This table shows the performance on a per call basis. For every call it gives call setup related parameters, for example start of call time, setup time, and so on. If the call is successful you can see how good or bad the call quality was.

Based on the quality parameters it also generates a CQI (call quality index). At the end of the table, there is a summary of the total calls and call wide summary.

Neighbor and Handover SummaryNeighbor Availability Statistics

This chart shows the analysis of neighbor availability.

It counts the number of neighbors reported above 97 dBm for every measurement sample, and on this count generates the histogram.

A high percentage value on the left of the chart means that coverage is not adequate and less cell signals are seen by the phone or the network parameters are not optimised.

Neighbor (Top 2 Strongest Received Level)

This histogram is a chart of the first and second strongest neighbor cells received signal level.

Band Usage

This chart shows the analysis of the frequency band used by the phone in the serving cell.

Handover Summary Statistics

This table shows a summary of analysis results on handover performance. It gives total calls, that are then divide the handover related count into:

Attempts

Completion

Failure

At foot of the table you are given the average number of inter-cell and intra-cell handovers per call.

Mobility Summary

This table indicates the mobility performance with a summary of the location update process and a count of the number of total cell re-selections.

Handover Graph

This is a line chart indicating the change in BCH values over time> This helps you see the handover methodology used during the drive test.

Handover to Strongest Neighbor Number

This chart indicates the probability of handovers happening to the 1st, 2nd and up to 6th strongest neighbors. Ideally the handovers should happen to the first or second neighbors but if more values are seen on the right side of the chart, then there is a possibility of congestion and neighbor non-suitability problems.

Cell Re-Selection Graph

This is a line chart indicating the cell change process, with Cell ID on the Y-axis.

Handover Drill DownHandover Cause Chart

The pie chart and table shows results from every handover. It shows handover related parameters, such as:

RxQual

RxLev

TA before the Handover

From these you can derive the estimated handover cause. The pie chart then summarises these estimated handover causes.

See alsoGSM Phone Reports - Details

The GSM phone menu option provides the following reports:

Executive Summary

This report provides three main sub reports:

Call Statistics Chart

This is a bar chart showing the results displayed in the Call Statistics details table. Statistics that highlight potential problem areas are highlighted in red.

Call Statistics Details

This provides a table values counted from the imported data. The values shown in this table are also displayed in the Call Statistics Chart above.

HYPERLINK "javascript:kadovTextPopup(this)" Click here for a list of values provided

Total Calls

Total Billable Calls

Blocked Calls

Dropped Calls

Total Cell Access

Successful Call Setups

Successful Channel Assignments

Total Disconnects

Total Drops

Handover Attempts

Handovers Successful

Handover Failures

Quality Performance Summary

This table shows you maximum, minimum, and average RF values from your imported measurement data. You are also provided all the values that have exceeded your preset threshold values, which are also shown.

Click here for a list of values provided

Phone State

No Service

Hopping

RxLev Full

RxLev Sub

N1 RxLev

N2 RxLev

RxQual Sub

FER

RLTC

Tx Level

Timing Advance

Overall Performance Summary

This report provides details on how well your network has been performing in of RF and signal quality. This report has 10 main sub reports:

Phone State

This is a bar chart showing the phone states found in your measurement data. The three states are:

Idle (Green)

Dedicated (Dark Blue)

No Service (Red)

DTX State

This is a bar chart showing the phone transmitter state during testing. The two states shown are:

Off (value "0") (Yellow)

On (value "1") (Green)

Hopping State

This is a bar chart showing the phone hopping states during testing. The two states shown are:

Hopping (Purple)

No Hopping (Maroon)

RxQual

This is a bar chart showing the ranges of RxQual found during testing. The states shown are:

0 (Green)

1 (Cyan)

2 (Cyan)

3 (Cyan)

4 (Violet)

5 (Red)

6 (Red)

7 (Red)

FER

This is a bar chart showing the ranges of FER found during testing. The states shown are:

0% (Green)

0 to 5% (Cyan)

5 to 10% (Cyan)

10 to 20% (Cyan)

20 to 40% (Violet)

40 to 70% (Red)

70 to 90% (Red)

90 to 100% (Red)

RxLev Full and RxLev Sub chart

(Dark Blue)

Timing Advance

0 to 1

1 to 5

5 to 10

10 to 20

20 to 35

35 to 50

50 to 63

All bars are shown in green.

RLTC Current Values

0

1

2

3 to 6

6 to 10

10 to 16

>16

0 is green, all others are red.

DSF Current Value Changes

0

1

2

3 to 6

6 to 10

10 to 16

>16

0 is green, all others are red.

Call Quality

This report provides information about call quality and call coverage. Selecting this report will provide the following information:

RxLev and RxQual variations

RxQual versus RxLev

Uplink performance estimation

Distance to coverage

Quality to handovers

Quality to BCCH

BCH versus BSIC

Quality versus TCH State

Performance By Cells

This report provides a table of performance results based on cell information.

Click here to see the table contents

Latitude

Min RxQual

Max TxLev

Longitude

Max RxQual

Average TxLev

Cell ID

Average RxQual

Min Timing Advance

% Availability

Average FER

Max Timing Advance

BCH

Min RxLev

Average Timing Advance

TCH State

Max RxLev

Min RLTC

Outgoing Calls

Average RxLev

Incoming Calls

Average N1 RxLev

Outgoing Handovers

Average N2 RxLev

Incoming Handovers

Min TxLev

Performance By Calls

This report provides a table of performance results based on call information.

Click here to see the table contents

Latitude

Longitude

Time

Call ID

Call Duration

CQI - Call Quality Index - Range 0-5, where 0 is poor and 5 is excellent

CellID of Start

BCH -Start

CellID End

BCH-End

TCH State

ARFCN

MAIO

Block Call

Drop Call Counter

Intra Cell Handovers

Inter Cell Handovers

Time of Service Request

Time of Call Setup

Time of Call Proceeding

Time of Alerting

Time of Disconnect Request

Time of Call Release

Time To Connect Calls

Time to Confirm instruction to connect

Time to Release Call

Min RxQual

Max RxQual

Avg RxQual

Min RLTC

Avg. FER

Min RxLev

Max RxLev

Avg RxLev

Avg N1 RxLev

Avg N2 RxLevel

Min TxLevel

Max TxLevel

Avg TxLevel

Min Timing Advance

Max Timing Advance

Avg Timing Advance

Handover and Neighbor Analysis

Handover Drill Down Analysis