1st optm

Optimization Trainning

Radio Dpt

BBU PARTS

BTS/NodeB Parts:

BBU Boards:

PM (Power Module): Provide power (12V, 3.3V) , measurement and protection of

input and overcurrent.

PM

BBU Boards:

SA (Site Alarms): This board perform monitoring, through

alarms of fan, lightning protection, dry contact interfaces,

channel interfaces (E1/T1).

SA

BBU Boards:

FS (Fabric Switch): This board provides baseband optical

interface between BBU and RRU. Also it process the IQ signal. FS

BBU Boards:

CC (Clock and Control): This board is used for controlling and

managing baseband unit through Ethernet and system clock.

CC

BBU Boards:

UPBG (Universal Processing Board for GMS): It processes the

physical layer protocol and frame protocol specified.

UPBG

BTS/NodeB Parts:

BBU Boards:

UPBG (Universal Processing Board for GMS) functions are:

Achieve rate adaptation, channel coding, interleaving, and

encryption.

Generate TDMA shock burst, GMSK/8PSK modulation, IQ

baseband digital signals output.

Achieve uplink IQ data receiving, receiver diversity combiner,

digital demodulation (GMSK&8PSK, equilibrium), decryption,

deinterleaving, demodulator, and rate adaptation. (GE Ethernet

interface transmits it to CC board for processing.)

Synchronize radio link, process transmission frame.

Measure parameters required in power control and handover.

BPC (Baseband Processing Type C): It is the main subsystem

due that here is where is physical layer processed from 3G. It

has function like: channel mapping, rate adaptation, modulation

and demodulation, etc.

BPC

NOTE: The only different between NodeB and BTS, in this case, is the

processing board, because the structure and architecture is the same.

BPC (Baseband Processing Type C) functions are:

Support 6 CS and 192 Channel Element. Encryption, rate adaptation, channel mapping, spread

spectrum, code mixing, modulation and demodulation

baseband signal spectrum..

Supports synchronous radio links and signal processing framework.

Power control. Transfer control software. Perform measurements for power control and transfer.

BPC type K = 12CS + 384 Channel Element.

PHYSICAL PARAMS

Azimuth

Crossfeeder

Crossfeeder on software

CELL IDENTIFIER

MCC LAC

Cell Global Identity

MNC

3 Digits 2-3 Digits Max 16 Bits

CI

Max 16 bits

LAI

CELL GLOBAL IDENTITY (CGI)

Cell Global Identity (CGI)

It is used for identifying individual cells within an LA

ROLES OF CGI

The CGI information is sent along the system broadcasting information in every cell.

When the MS receives the system information, it will extract the CGI information from it and determines whether to camp on the cell according to the MCC and MNC specified by the CGI.

It judges whether the current location area is changed, then determines whether to take the location updating process.

RATs (Radio Access Technology)

(received signal strength indicator)

(Absolute Radio Frequency Channel Number)

2G 3G

RSSI

ARFCN

RSCP

Ec/No

UARFCN

PSC

(received signal code power)

(Energy Chip / Noise)

(UTRA ARFCN)

(Primary Scrambling Code)

3G

RSCP

Power measured

Indication of signal strength

HO criterion

Power Control

Path loss

Measured by UE reported to NodeB

3G

EcNo (Energy per chip/Total Noise power density)

How good is link quality

RSCP = RSSI(in UMTS signal power over 5Mhz) + Ec/No

Ec/No = RSCP RSSI

3G

PSC (Primary Scrambling Code)

UE determines the exactly PSC used by the found cell.

UE to get PSC: 1st step: Slot synchronization (UE uses SCHs 1st primary

synchronization code to acquire slot synchronisation to a cell. )

2nd step: Frame synchronisation and code-group identification (SCH's secondary synchronisation code to find frame synchronisation and identify the code group of the cell found in the first step).

3rd step: Scrambling-code indentification.

Bitel 3G Spectrum Planning

900MHz 899-915 MHz / 944-960 MHz (Lima y Callao)

902-915 MHz / 947-960 MHz (Lima provincia y provincias)

1900MHz: 1897.5-1910MHz / 1977.5-1990 MHz

3G

UARFCN:

3035

3060

3085

9910

9935

Frecuencia

902 - 947

907 - 952

912 - 957

1902 - 1982

1907 - 1987

GSM900/1800: 3G (WCDMA):

Single Frequency Network

Radio Transmission Technology Requirements

Data 144 kbps High speed and driving 384 kbps Modest speed and walking 2 Mbps Low speed and indoor

Voice 4.75Kb/s -- 12.2Kb/s 64kb/s (Video Phone)

Information transmission at variable rate according to bandwidth requirements

Delay requirements of different service

3G services

Delay

Bit Error

Different QOS requirements

3G services Categories Actual Service Delay (One-way) Bearer Speed

conversational

Voice

Multiple Access Technologies

Why Multiple Access? Increased capacity: serve more users Reduced capital requirements since fewer

media can carry the traffic Decreased per-user expense

Types of Transmission Medium: Twisted pair Coaxial cable Fiber optic cable Air interface (radio signals)

Three methods are frequently used: FDMA TDMA CDMA

Each pair of users enjoys

a dedicated, private circuit

through the transmission

medium, unaware that the

other users exist.

Transmission

Medium

Multiple access technologies enable various users access public communication line but without interference.

Freq. 1

Freq. 1

BS1

BS2

Code D

CDMA Application

Users are distinguished by scrambling codes and OVSF codes

Self-interference system

CDMA system is restricted to interference (GSM system is restricted to frequency resources)

radio channel

Receiver Transmitter

Spreading

Despreading

Noise

Spread Spectrum Principles

User information bits are spread over a wide bandwidth by multiplying high speed spread code(chip)

Spread signal bandwidth W wider than original signal bandwidth Rb

f

Sf

f0

Before spreading

signal

Sf

f f0

After spreading

signal

Sf

f f0

After despreading

signal

White noise

f

Sf

f0

Before despreading

signal

White noise

signal interference White noise



Many code channels are individually

spread and then added together to

create a composite signal

Characteristics of Spreading Communication

High anti-multi-path- interference capability

Anti-sudden-pulse

High security

Lower transmitting power

Easy to implement large-capacity Multiple Access Communication

Occupy band wide

Complex realization

Purpose of Channel Coding

By adding redundant information in the original data stream, receivers can detect and correct the error signal, and improve data transmission rates.

No correct coding: BER

Principle of Channel Coding

Channel coding

Error-correcting ability obtains by adding redundancy in the original data

Convolutional coding and Turbo coding 1/21/3 are widely applied.

Increase noneffective load and transmission time

Suitable to correct few non-continuous errors

W C D M A

T U R B O

S P E A K

W W C C D D M M A A

T T U U R R B B O O

S S P P E E A A K K

W ? C C D D M M A A

T T ? U R R B B O O

S S P P E E A ? K K

Decoding

Encoding

Encoding and Interleaving

W C D M A

T U R B O

S P E A K

W W C C D D M M A A

T T U U R R B B O O

S S P P E E A A K K

W T S W T S

C U P C U P

D R E D R E

M B A M B A

A O K A O K

W ? ? C D D M M A ?

T ? ? U R ? ? B O O

S ? ? P ? E A A K K

Encoding Interleaving

W T S ? ? ?

? ? ? C U P

D R ? D ? E

M ? A M B A

A O K ? O K

Deinterleaving Decoding

Encoding + Interleaving can correct both

continuous and non-continuous errors

Principle of Modulation

Definition Modulation is the process where the amplitude,

frequency, or phase of an electronic or optical signal carrier is changed in order to transmit information.

Using symbol stand for one or more bits to improve communication effectiveness

Classification Analog Modulation

Digital Modulation

Symbol bit Modulation

Analog Modulation The purpose of analog modulation is to impress an information-

bearing analog waveform onto a carrier for transmission. Common analog modulation methods include:

Amplitude modulation (AM)

Frequency modulation (FM)

Phase modulation (PM)

The purpose of digital modulation is to convert an information-bearing discrete-time symbol sequence into a continuous-time waveform (perhaps impressed on a carrier). Basic analog modulation methods include

Amplitude shift Keying (ASK)

Frequency shift Keying (FSK)

Phase shift Keying (PSK)

Digital Modulation

WCDMA Data transmission Procedure

RF Receiving Demodulation Despreading

Decoding &

De-inteleaving UE Data

UE Data Spreading

RF Transmitting

Modulation

Baseband

demodulation

Baseband

modulation

Encoding &

Interleaving

Symbol rate SF = Chip rate=3.84Mcps

For UMTSSF of uplink channelization code4~256

SF of downlink channelization code: 4~512

OVSF: Orthogonal Variable Spreading Factor

OVSF Code Scrambling Code

Data Spread Data

Spreading Process of UMTS

Symbol Chip

3.84Mcps

3.84Mcps

Channelization Code

Adopt OVSF code

Definition: Cch,SF,k, describe channelization code, where

SF : spread factor k : code number, 0 < k

Scrambling Code UMTS Scrambling code is pseudo random binary sequence

It has similar noise array character, seemingly random but with regularity.

Can make the user data further random , strengthened by scrambling a code to keep secret the user data, at the same time easy to carry out multiple access communication.

UMTS scrambling code is generated from Gold sequence

Gold sequence has excellent self-correlation. Cross-correlation is very weak between two codes. It is used to identify cell and user for multiple access.

Characteristic of Scrambling code

There are 224 Uplink Scrambling Codes, they are used to distinguish different users in one cell.

There are 218-1 Downlink Scrambling Codes, used to distinguish different cells Scrambling codes usually used are the first 8192 codes,

which are code 018191. They are divided into 512 aggregationseach aggregation has 1 primary scrambling code (PSC) and 15 secondary scrambling codes (SSC).

The 512 primary scrambling codes are divided further into 64 primary scrambling code groups , with 8 primary scrambling codes in each group.

Numbering rule for Downlink Scrambling Codes

218

-1 Downlink Scrambling Codes in all

(0..262142)

No. 511 Scrambling Code

Group

8176

8177

8191

8176PSC

8177SSC

8191SSC


Group

8160

8161

8175

8160

8161

8175


Group

8064

8065

8079

8064

8065

8079


Group

112

113

127

8176PSC

8177

8191


Group

16

17

31

16PSC

17SSC

31SSC


Group

0

1

15

0PSC

1SSC

15SSC

No.63 Primary Scrambling Code Group

No.0 Primary Scrambling Code Group

Code Functions

Channelization code

Uplink: for separation of physical channels

Downlink: separation of users

Scrambling code

Uplink: for separation of users/terminals

Downlink: separation of cells/sectors in the downlink.

Modulation Methods in UMTS

BPSK (Binary Phase Shift Keying) in Uplink channles

QPSK (Quadrature Phase Shift Keying) in Downlink channels

16QAM (16-state Quadrature Amplitude Modulation) in HSDPA

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