Patent ID: 7158578

Claim:
An IQ modulator for modulating in-phase (‘I’) and quadrature-phase (‘Q’) components of an input signal in accordance with I and Q symbols, comprising: I and Q FIR means for filtering the I and Q signal components, respectively, and generating I and Q sets of FIR components (x1d–x4d) corresponding to said I and Q input signal components multiplied by sets of coefficients, said FIR means operating at the symbol rate; and a polynomial waveform generator comprising I and Q accumulator means, said I and Q accumulator means comprising I and Q sets of first accumulator elements and I and Q second accumulator elements, said I and Q sets of first accumulator elements being arranged to load said I and Q FIR signal components at the symbol rate and accumulate at an over-sampling rate so as to calculate first order derivatives, and said I and Q second accumulator elements being arranged to accumulate progressively, without reinitialization except at a beginning of a transmission burst, the outputs of said I and Q sets of first accumulator elements and produce therefrom I and Q signal components modulated with the I and Q symbols.