Patent ID: 7970062

Claim:
A method of distributing high-bandwidth and low-bandwidth voice channels comprising: receiving an input signal; separating the input signal into a first high-band signal and a first low-band signal, wherein the separating the input signal into a first high-band signal and a first low-band signal is done by way of a decomposition portion of a Quadrature Mirror Filter (QMF), wherein the decomposition portion of the QMF comprises: an amplifier receiving the input signal and providing an amplifier output signal; a first low-pass filter coupled to the output of the amplifier, the first low-pass filter receiving the amplifier output signal and producing a low-pass signal; a first down-sampler coupled to the low-pass filter, the first down-sampler receiving the low-pass signal and providing the first low-bandwidth signal; a delay coupled to the amplifier and receiving the amplifier output signal, the delay producing a delayed signal; a first high-pass filter coupled to the output of the delay, the first high-pass filter receiving the delayed signal and producing a high-pass signal; and a second down-sampler coupled to the high-pass filter, the second down-sampler receiving the high low-pass signal and providing the first high-bandwidth signal; compressing the first low-band signal to provide a low-bandwidth channel; and carrying encoded voice signals on the low-bandwidth channel.