Abstract: There is disclosed a signal scrambling transmission system in which the data is scrambled at the transmit end by logically combining the data with a pseudo random sequence generated by a ROM prior to transmission. The data is recovered at the receive end by logically combining the scrambled data with the same pseudo random sequence generated by a ROM. The ROM at the transmit end is divided into frames with a synchronization word and a frame count (index) word embedded in each frame. The synchronization word and index word are transmitted with each frame of data and are used to synchronize the ROM at the receive end with the incoming scrambled data. The transmit end ROM is divided into 32 frames each being 4,096 bits long. Each frame has a 27-bit synchronization word, a 5-bit index word, and 4,064 bits of pseudo random sequence.

Abstract: There is disclosed an analog signal processing circuit (compandor) and a method for overcoming noise in a transmission medium by means of a composite compressor and composite expander. The composite compressor splits the frequency spectrum of the analog signal into two or more frequency components, compresses all of the frequency components in parallel with the same 3:1 integer compression ratio, combines the compressed frequency components to produce a compressed analog signal, and transmits the compressed analog signal on the transmission medium.