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PIAM, Jorge García Vidal
PIAM, Jorge García Vidal
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Recepción correcta
Recepción incorrectaPosible interferencia
La señal radio se atenúa fuertementecon la distancia.Se transmite en broadcast(directividad de antenas)
Potencia
Distancia a la antena
4
PIAM, Jorge García Vidal
Distancia a la antena
Potencia de señal recibida
Potencia mínima
Potencia de ruido
Relación señal a ruido (SNR) = P recibida/P de ruido
Rango máximo
PIAM, Jorge García Vidal
Distancia a la antena
Potencia de señal recibida
Potencia mínima (vel de transmisión alta)
Potencia mínima (vel de transmisión baja)
Nos podemos alejar más si disminuimosLa velocidad de transmisión
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Grandes variacionesen la intensidad de laseñal recibida
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Por ejemplo, en 802.11a, para tramas de 512, backoffBackoff = CWmin/2 & 64 QAM 3/4…
Throughput = 0.28 x 54 Mbps = 15.5 Mbps (!)
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