Telecommunications – Transmitter and receiver at separate stations
Patent
1993-11-03
1996-04-09
Faile, Andrew I.
Telecommunications
Transmitter and receiver at separate stations
455 43, 455 93, 375222, 375296, 379 59, 379 98, H04M 1100, H04B 100
Patent
active
055070337
ABSTRACT:
A system and method for reducing amplitude distortion in a data signal transmitted through a cellular analog communication system is embodied in several forms. Each specific embodiment of the invention eliminates distortion caused by clipping or sluggish recovery time induced by a limiter circuit which exists in conventional cellular communication systems. In one embodiment, pre-emphasis and de-emphasis functions of the cellular system are offset by complementary de-emphasis and post-emphasis circuits so that the high frequency components of the data signal are not clipped by the limiter. In another embodiment, the limiter circuit is bypassed selectively when a data signal is transmitted. In an alternative embodiment, a pilot tone is combined with the incoming data signal. The characteristics of the pilot tone are such that amplitude of the pilot tone is constant and always sets the gain of the limiter, thereby keeping the gain of the limiter circuit constant.
REFERENCES:
patent: 3109991 (1963-11-01), Ocko
patent: 3111635 (1963-11-01), Skov et al.
patent: 3444469 (1969-05-01), Miyagi
patent: 3517314 (1970-06-01), Miyagi
patent: 3962638 (1976-06-01), Sallis
patent: 4051438 (1977-09-01), Pickett et al.
patent: 4053717 (1977-10-01), Snider
patent: 4110692 (1978-08-01), Pradal
patent: 4215431 (1980-07-01), Nady
patent: 4481547 (1984-11-01), Sato
patent: 4578818 (1986-03-01), Claydon
patent: 4754230 (1988-06-01), Schwartz et al.
patent: 4802236 (1989-01-01), Walczak et al.
patent: 4860336 (1989-08-01), D'Avello et al.
patent: 4893349 (1990-01-01), Eastmond et al.
patent: 4907087 (1990-03-01), Schreiber
patent: 5042085 (1991-08-01), Errico
patent: 5058202 (1991-10-01), Leveque
patent: 5127041 (1992-06-01), O'Sullivan
patent: 5168516 (1992-12-01), Ito
patent: 5204970 (1993-04-01), Stengel et al.
patent: 5214641 (1993-05-01), Chen et al.
patent: 5226178 (1993-07-01), Eastmond et al.
patent: 5257397 (1993-10-01), Barzegar et al.
patent: 5297192 (1994-03-01), Gerszberg
patent: 5386590 (1995-01-01), Dolan
OKI Electric Industry Co., Ltd. (Japan): "Proposal for Modem Evaluation System Over Cellular Radio Links," CCITT Study Group XVII, Delayed Contribution D 137, Geneva, Oct. 29-Nov. 6, 1991, pp. 1-4.
Article entitled "Performance Testing of Cellular Modems", by Mike Mukund and Fred Mohajer, from Test & Measurement World, dated Jan. 1993, pp. 63, 64, 66, 68 and 69.
Telebit Corporation: "The Static Characteristics of Analog Cellular Radio Channels and Their Effects Upon Data Transmission," CCITT Study Group XVII, Delayed Contribution D 1;36, Geneva, Oct. 29-Nov. 6, 1991, pp. 1-11.
EIA Interim Standard, "Recommended Minimum Standards for 800=MHZ Cellular Subscriber Units," EIA/IS-19-B, May 1988.
Celeritas Technologies, Ltd.
Faile Andrew I.
LandOfFree
Apparatus and method for increasing data transmission rate over does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for increasing data transmission rate over , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for increasing data transmission rate over will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-147486