Modulation  

Dear Friends,
Can any one share the info about the ideal values of CINR and RSSI vaule at different bandwidth and modulation.

Bandwith : 3 , 3.5 ,6 6.5 MHz
Modulation :
BPSK ½
QPSK ½
QPSK ¾
QAM 16 ½
QAM 16 ¾
QAM 64 2/3
QAM 64 ¾

please note that the values differ from vendor to fendor.
The following table referes to a 3.5MHz BW System:
Typical levels for BER <1x10-6 are given.

Modulation / FEC / Rx Sensitivity / CINR
64QAM 3/4 -80.0dBm 23.0dB
64QAM 2/3 -82.0dBm 21.0dB
16QAM 3/4 -86.0dBm 17.0dB
16QAM 1/2 -88.0dBm 15.0dB
QPSK 3/4 -92.0dBm 11.0dB
QPSK 1/2 -94.0dBm 9.0dB
BPSK 1/2 -98.0dBm 5.0dB

these values are for BER <1x10 E-6, and they tend to produce a packet loss of about 1x10 E-2 which is fine for TCP, but a murder for UDP/RTP multimedia.
Also, consider faster scheduling types in case multimedia is a key role of your network. Check for performance with short packets - ther may be some surprises with latencies and throughput ;)

This information is provided by the vendor. The vendor will provide a minimum signal strength to achieve each modulation/coding scheme.

The noisie floor is dependant of the bandwidth (-174 + 10logBW/hz) plus the Noise Figure of the receive amplifier. The NF will vary by vendor and will also vary if set at the top of the tower (close to the antenna) or on the ground (typically in the base station).

Frequency reuse will increase the signal strength requirement (S/N+I)

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