Patent ID: 6795692
Filing Date: 2004-09-21
Classification: H04B

Abstract:
A method for transmitting information in a radio system using a middle channel, a first side channel and a second side channel each containing information, the radio system including a channel transmitter unit and a channel receiver unit configured to operate at a plurality of radio frequencies, comprising the steps of:defining a frequency band width of the middle channel; defining, for each of the first and second side channels, a frequency band width that is no larger than the frequency band width of the middle channel; using a suitable modulation frequency to frequency modulate the middle channel; generating an amplitude-modulated signal that is symmetrical with respect to a center frequency of the middle channel and comprising a middle wave, an upper single side band and a lower single side band; suppressing the middle wave and the upper single side band of the amplitude-modulated signal to generate a first amplitude-modulated single side band (LSB) by taking a sample of the middle wave and the upper single side band, reversing a phase of the sample and summing it with the amplitude-modulated signal; suppressing the middle wave and the lower single side band of the amplitude-modulated signal to generate a second amplitude-modulated single side band (USB) by taking a sample of the middle wave and the lower single side band, reversing a phase of the sample and summing it with the amplitude-modulated signal; modulating the first amplitude-modulated single side band (LSB) by the information in the first side channel to form two side bands for the first single side band; modulating the second amplitude-modulated single side band (USB) by the information in the second side channel to form two side bands for the second single side band; and combining the frequency-modulated middle channel, the modulated first single side band and the modulated second single side band in a combiner for simultaneous transmission of a combined signal comprising the frequency-modulated middle channel and the modulated first and second single side bands.