Patent ID: 6307893
Filing Date: 2001-10-23
Classification: H04L

Abstract:
A system for shaping a transmit signal spectrum, comprising:a filter having a set of filter coefficients defining a particular transmit spectrum, said filter designed to receive as input a signal space mapped flat spectrum signal, said filter designed to process said signal space mapped flat spectrum signal and output a precoded signal having a desired precoded signal spectrum;a feedback loop containing a modulo operation designed to operate on said precoded signal from said filter, said modulo operation designed to restrict the magnitude of said precoded signal resulting in a substantially flat spectrum signal;a subtractor designed to subtract the output signal of said modulo operation from a signal space mapped signal resulting in said signal space mapped flat spectrum signal; andan adder designed to add the output of said filter to said signal space mapped flat spectrum signal, said adder designed to output a precoded transmit signal that meets a desired signal spectrum;wherein, the precoded transmit signal is the output of the system for shaping the transmit signal spectrum.