Patent ID: 6216107
Filing Date: 2001-04-10
Classification: H04L

Abstract:
A method of transmitting a digitized signal across a radio channel, comprising:encoding a digitized signal comprising a binary bit stream having bits classified as one of critical, important and unimportant, at a first rate;expanding the encoded digitized signal to a second rate greater than the first rate and according to bit classification by deriving parity bits from the critical bits;encoding the parity bits with a 1/6 rate convolutional encoder to produce a first output signal;combining the critical and important bits and adding six tail bits to produce a second output signal;encoding the second output signal with a 1/4 rate convolutional encoder to produce a third output signal;encoding the unimportant bits with a 1/2 rate convolutional encoder to produce a fourth output signal;encoding the first, third and fourth output signals to produce the expanded digitized signal at the second rate; andtransmitting the expanded digitized signal at the second rate across a radio channel.