Title:
【発明の名称】4相位相変調符号化装置
Document Type and Number:
Japanese Patent JPH0685535
Kind Code:
B2
Abstract:
The quadriphase phase modulation system comprises a serial to parallel (S/P) converter (1) for converting serial input data into one-symbol two-bit parallel data, and a waveform generator (6) for generating waveform information corresponding to a bit pattern created by the current symbol of the S/P converter (1) and a symbol prior to this current symbol. A memory (4) stores a first waveform determined by the current symbol and the symbol prior to the current symbol and a second waveform determined by the current symbol. Then, the memory (4) supplies the waveform corresponding to the current symbol in response to the waveform information. A digital to analog converter (5) converts signals from this memory (4) into analog signals. This system is capable of generating phase modulation signals which are narrow in bandwidth without the need for a band-limiting filter.
Inventors:
KOIKE SHINICHI
Application Number:
JP23860585A
Publication Date:
October 26, 1994
Filing Date:
October 26, 1985
Export Citation:
Assignee:
NIPPON ELECTRIC CO
International Classes:
H03M5/22; H04L25/49; H04L27/18; (IPC1-7): H04L25/49; H04L27/18
Domestic Patent References:
| JP59161157A |
Attorney, Agent or Firm:
Tan Ashida (2 outside)
Next Patent: 副信号伝送方法