Multi - tone signal transmission methods and apparatus

A multi-tone signal communications method for communicating information using N tones, where N is a positive integer greater than one, the method comprising:

• generating in parallel, for each one of the N tones, a separate periodic signal including at least one high order harmonic signal component that is different from the fundamental frequency signal component of said tone;
• and
• transmitting the generated N periodic signals into a communications channel.

A multi-tone signal communications method for communicating information using at least N tones, where N is a positive integer greater than one, the method comprising:

• separately generating, for each one of the N tones, a passband periodic signal representing a symbol;
• and
• transmitting the N generated passband periodic signals.

A method of broadcasting signals representing tones of an N tone multi-tone signal, for a first period of time corresponding to multiple symbol transmission periods and for a second period of time also corresponding to multiple symbol transmission periods, where N is a positive integer greater than one and the tones in the N tone multi-tone signal are fixed for the first and second periods of time but include different tones in each of the first and second periods of time, the method comprising:

• broadcasting signals corresponding to different tones of the N tone multi-tone signal during the first period of time using a fixed first set of M different antennas where M is an integer and where M<N;
• and
• broadcasting signals corresponding to different tones of the N tone multi-tone signal during the second period of time using a fixed second set of M different antennas, at least one antenna in the fixed second set of M different antennas being different from the antennas included in the fixed first set of M different antennas.

A method of sequentially transmitting symbols in a multi-tone signal communication system using N tones per symbol period, wherein the N tones remain the same for multiple symbol periods, the time period in which the N tones remain the same being a dwell, the method comprising:

• for each symbol transmission period of the dwell:
• transmitting N signals corresponding to each one of the N tones of the multi-tone signal, each one of the N signals being transmitted on a corresponding one of a first plurality of antennas, the antenna being used to transmit signals corresponding to a particular tone during the dwell remaining the same throughout the dwell.

A transmitter for broadcasting a signal corresponding a multi-tone signal, the transmitter comprising:

• a plurality of first through Nth periodic signal generators for generating periodic passband signals representing symbols, where N is a positive integer greater than 1, each one of the N periodic signal generators generating a periodic signal having a frequency corresponding to a different one of N tones of said multi-tone signal;
• and
• a plurality of M antennas, where 1<M≦N, each one of the M antennas being coupled to at least one of the first through Nth periodic signal generators, each periodic signal generator being coupled to a single one of said M antennas.

A system for generating and transmitting signals corresponding to an N tone multi-tone signal, where N is a positive integer greater than 1, the system comprising:

• N periodic signal generator circuits for generating periodic signals, each periodic signal corresponding to a different tone one of the N tones of the multi-tone signal;
• and
• N prefix generator circuits for independently generating periodic signal prefixes, each one of the N prefix generator circuits being coupled to a different corresponding one of the N periodic generator circuits.