Coding system for digital transmission compression

摘要

An improved coding system for digital transmission compression applicable as a digital compression algorithm for increasing the bandwidth of telecommunications and broadcasting networks. The improved coding system operates in the transmission regime, not in baseband (source) so that a transmission channel having a capacity of 1 Mbit/s can deliver N Mbit/s, where N bits in parallel are combined to be delivered in the 1 Mbit/s channel. The system includes the steps of simultaneously encoding a first group of parallel binary bits into a digitized voltage amplitude signal in a predetermined bit interval, modulating a carrier with the digitized voltage amplitude signal, transmitting the modulated carrier over a bandwidth limited communications highway having intrinsic noise therein, demodulating said modulated carrier signal and receiving said digitized voltage amplitude signal, said demodulating means substantially cancelling said intrinsic noise and improving said output signal to noise ratio; and decoding the digitized voltage amplitude signal received in the predetermined bit interval into a second group of parallel binary bits which correspond to the first group of parallel binary bits. The digital compression algorithm is applicable to telephone networks, including telephone twisted pair (TTP) wiring, coaxial cables for telephony, data transmission, and video transmission with or without accompanying sound; microwave, cellular, mobile, and personal communications networks; radio and satellite networks and can be realized physically in very-large-scale-integrated (VLSI) chips.