Signal equalizer for a signal transmission network

In a radio frequency (RF) signal transmission network for transferring symbols comprising:

• an RF transmission medium for transmitting the symbols modulated to a transmission format;
• and at least one adaptive equalizer for filtering inter-symbol interference (ISI) in the transmitted signals, the adaptive equalizer having a series of coefficients for which values are required;
• a method for initializing the adaptive equalizer coefficients comprising:
• using a parallel filter structure to construct a model of the transmission channel so as to decompose the model of the transmission channel into two segments, each of which is represented by a single FIR filter, thereby modeling the ISI seen at the receiver as two symbol-rate FIR filters connected in a parallel configuration;
• transmitting a signal preamble including symbols arranged such that the required equalizer coefficients can be calculated;
• wherein both the channel model and the equalizer are both represented with only a single sample per symbol;
• wherein the calculation is arranged to calculate coefficients b for the ISI equivalent model;
• and wherein the calculation includes using a circuit to effect calculation of the required equalizer coefficients from the coefficients b for the ISI equivalent model.