Patent ID: 8175190

Claim:
A method for operating a first communication node, the method comprising: encoding information bits to obtain encoded bits, wherein the encoded bits represent the information bits with redundancy; modulating the encoded bits onto frequency components of a signal, wherein an amplitude of each of the frequency components is determined by a corresponding subset of the encoded bits, the resulting modulated signal including at least some redundancy in frequency enabling a portion of the encoded bits modulated onto selected ones of the frequency components to be recovered from fewer than all of the selected frequency components; controlling the spectrum of the modulated signal, including attenuating amplitudes at respective carrier frequencies of at least some of the frequency components of the modulated signal by setting those amplitudes below a predetermined amplitude used for modulating the encoded bits; generating the modulated signal using a transform that includes the frequency components with amplitudes that have been set below the predetermined amplitude; and transmitting the modulated signal from the first communication node to a second communication node, wherein the second communication node is able to recover the portion of the encoded bits without knowledge of whether any of the selected frequency components have been set below the predetermined amplitude used for modulating the encoded bits.