Binary convolutional encoder of cable modem downstream system TCM encoder

摘要

The present invention relates to a binary convolutional encoder having characteristics of G1 (= 010101), G2 (= 011111) generation code, 16 states, and 1/2 bit rate in a cable modem downstream system TCM encoder.;The apparatus of the present invention comprises four memories 51 to 54 and two multiplexers 55 and 56 connected in series, each memory 51 to 54 delaying an input signal by one clock to the next memory. The first multiplexer 55 selects 0 or 1 in accordance with a 3-bit control signal that is an output signal of the encoder, an output of the second memory 52, and an output of the fourth memory 54 to select the first multiplexer 55. The output signal Y1 is output, and the second multiplexer 56 selects 0 or 1 according to the input signal of the encoder and the 5-bit control signal that is the output of the first to fourth memories 51 to 54, thereby selecting the second of the encoder. Output the output signal Y2.;Therefore, the present invention has the effect of efficiently designing a binary convolutional coder by using a control signal according to the generation code of the coder without separately designing an exclusive logic operator for convolutional coding with respect to the output signals Y1 and Y2. .