公开(公告)号：GB2260671B

公开(公告)日：1995-05-24

申请号：GB9225110

申请日：1992-03-09

Applicant: MOTOROLA INC

Inventor： LEMERSAL JR DONALD B ,  WALCZAK THOMAS J ,  GREENE ROBERT I

IPC: H04L27/20

Abstract: A modulator circuit for generating a modulated, DQPSK signal. The modulator circuit includes an encoder for receiving a binary bit stream comprised of bit pairs defining differential phase changes. An encoder receives a bit stream of which bit pairs thereof define differential phase changes. The encoder encodes the bit pairs into codewords which are stored and then supplied to an I-accumulator, a Q-accumulator, and a memory element. The memory element contains pre-multiplied values which are supplied to the I- and the Q-accumulators which add terms of the pre-multiplied values to form I-portions and Q-portions of a DQPSK-modulated signal. The I- and Q-portions may then be supplied to a quadrature modulator.

公开(公告)号：GB2260671A

公开(公告)日：1993-04-21

申请号：GB9225110

申请日：1992-03-09

Applicant: MOTOROLA INC

Inventor： LEMERSAL JR DONALD B ,  WALCZAK THOMAS J ,  GREENE ROBERT I

IPC: H04L27/20

Abstract: A modulator circuit (150) for generating a modulated, DQPSK signal. The modulator circuit includes an encoder (162) for receiving a binary bit stream comprised of bit pairs defining differential phase changes. An encoder receives a bit stream of which bit pairs thereof define differential phase changes. The encoder encodes the bit pairs into codewords which are stored and then supplied to an I-accumulator (230), a Q-accumulator (236), and a memory element (242). The memory element contains premultiplied values which are supplied to the I- and the Q-accumulators which add terms of the pre-multiplied values to form I-portions and Q-portions of a DQPSK-modulated signal. The I- and Q-portions may then be supplied to a quadrature modulator.