Network performance is ultimately defined by the radio capability to recover the original information. A radio is made of RF hardware and a signal processing hardware and software. The RF hardware has a defined SNR (Signal to Noise Ratio) to be able to extract the information from the received signal. Typical examples are a SINAD (Signal to Interference Noise And Distortion) of 12 dB for FM signals.
The signal processing hardware and software pre-process the information before transmitting it to improve the chances of recovery, by using error correction codes, interleaving and scrambling. All this results in different SNR requirements for different environments and different error rates, for each possible throughput. Due to this, radio performance has to be estimated for all possible operating conditions. In this chapter we cover how this estimation can be done. This methodology was derived from the CelPlanner software developed by CelPlan Technologies.
Basic radio performance can be defined by its Receive Sensitivity, which is the minimum input signal that results in an output with a desired signal to noise ratio and is defined by Equation (11.1).
(11.1) Receiver sensitivity
Si = Sensitivity in Watt.
k = Boltzmann's constant (1.38 × 10−23 J/K).
Tt = Source thermal noise at input (290°K).
TRX = Equivalent noise temperature ...