Level control circuit for portable radio communication apparatus

Details Level control circuit for portable radio communication apparatus Level control circuit for portable radio communication apparatus

1995-11-27

1999-06-29

Tung, Bryan

Telecommunications

Receiver or analog modulated signal frequency converter

Local control of receiver operation

4552511, 455323, 4552321, 4552411, 4552532, H04B 104

Patent

active

059181664

ABSTRACT:
A compact level control circuit without using a shield structure is suitably provided in a small space such as a portable radio communication apparatus. A level control circuit for a portable radio communication apparatus arranged by: a first variable attenuator into which an input RF (radio frequency) signal is supplied, the attenuation amount of which is controlled based upon a first level control signal, and which outputs a first attenuated RF signal; a frequency converter for frequency-converting the first attenuated RF signal into a predetermined intermediate frequency band signal to thereby output a first IF (intermediate frequency) signal; a second variable attenuator into which the first IF signal is supplied, the attenuation amount of which is controlled based on the first level control signal, and which outputs a second attenuated IF signal; and a bandpass filter for outputting only said predetermined intermediate frequency band component of the second attenuated IF signal.

REFERENCES:
patent: 4553105 (1985-11-01), Sasaki
patent: 4665560 (1987-05-01), Lange
patent: 5107487 (1992-04-01), Vilmur et al.
patent: 5307512 (1994-04-01), Mitzlaff
patent: 5457811 (1995-10-01), Lemson
patent: 5513387 (1996-04-01), Saito

Affiliated with

Also associated with

Rating

Level control circuit for portable radio communication apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Level control circuit for portable radio communication apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Level control circuit for portable radio communication apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1386664