Title:
RECEIVER WITH DEMODULATING CIRCUIT
Document Type and Number:
Japanese Patent JPH0678012
Kind Code:
A
Abstract:
PURPOSE: To reduce variation in a demodulated signal caused by fading or the like as less as possible.
CONSTITUTION: A detection circuit part 10 limits the amplitude of an inputted GMSK/ASK signal to be modulated by a limiter amplifier 11, detects its frequency by an FM detector 12 and outputs a GMSK detected signal. Simultaneously the circuit part 10 detects an envelope by an AM detector 13, executes the logarithmic conversion of the envelope by a logarithmic converter 14 and outputs an amplitude-detected signal. A band pass filter(BPF) 20 passes an ASK modulated signal component included in the amplitude detected signal but removes an unnecessary amplitude variation component generated caused by fading or the like.
Inventors:
TAKAHASHI JUNICHI
HATASHITA HIROSHI
NAGASHIMA TOSHIO
HATASHITA HIROSHI
NAGASHIMA TOSHIO
Application Number:
JP22698992A
Publication Date:
March 18, 1994
Filing Date:
August 26, 1992
Export Citation:
Assignee:
HITACHI LTD
International Classes:
H03D5/00; H04L27/32; (IPC1-7): H04L27/32; H03D5/00
Attorney, Agent or Firm:
Namiki Akio
Next Patent: QUADRATURE AMPLITUDE-MODULATED DATA RECEIVER