Patent ID: 7324604

Claim:
A method for shaping a spectrum of an impulse radio signal, comprising: generating a set of ultrawide bandwidth basis pulses at a plurality of frequencies and a plurality of random delays; optimizing, jointly, weights and delays as a solution to a quadratic optimization problem to approximately minimize a deviation of the spectrum from a spectral mask an ultrawide bandwidth spectral mask, in which the spectral mask is designed for indoor channels and limits power as a function of frequency in the spectral mask; orthogonalizing and normalizing the set of ultrawide bandwidth basis pulses; and applying a branch and bound procedure to the set of orthogonalized and normalized ultrawide bandwidth basis pulses to optimize the delays; weighting the set of ultrawide bandwidth basis pulses by the weights; delaying the set of basis pulses by the random delays; and combining linearly the weighted and delayed basis pulses to conform the spectrum to the ultrawide bandwidth spectral mask, and wherein the weights and delays are fixed over time for the spectral mask, and wherein the ultrawide bandwidth basis pulses are selected from a set of basis pulses by a combinatorial optimization using training spectral masks.