Telecommunications – Transmitter and receiver at same station – With a common signal processing stage
Patent
1996-06-26
1999-11-16
Mullen, Jr., Thomas J.
Telecommunications
Transmitter and receiver at same station
With a common signal processing stage
375219, 370294, H04B 140
Patent
active
059873094
ABSTRACT:
A transceiver circuit with a heterodyne receiver circuit is provided. Output signals of first and second local oscillator 103, 104 are mixed by a local frequency converter 105. An output signal of the converter 105 passes a filter 106 and inputs a modulator 111 of a transmitter circuit 101 as well as a first frequency converter 122 of a receiver circuit 102. The second local oscillator 104 comprises a frequency synthesizer whose output signal varies for a transmission or a receiving mode. The output signal of the second local oscillator 104 also inputs the second frequency converter 124 of the receiving mode. A reference frequency of the second local oscillator 104 is set higher than a frequency step between communication channels so that a quick switching of the frequency is performed. Thus, the transceiver circuit of this invention is suitable for a compact size and hardly generates unwanted spurious components at transmission mode.
REFERENCES:
patent: 4186344 (1980-01-01), Higuchi et al.
patent: 4979170 (1990-12-01), Gilhousen et al.
patent: 5339309 (1994-08-01), Saito
patent: 5444865 (1995-08-01), Heck et al.
patent: 5657344 (1997-08-01), Na
Adachi Hisashi
Kosugi Hiroaki
Morinaga Youichi
Obara Toshio
Matsushita Electric - Industrial Co., Ltd.
Mullen Jr. Thomas J.
LandOfFree
Transceiver circuits for TDMA system with variable frequency sec does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transceiver circuits for TDMA system with variable frequency sec, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transceiver circuits for TDMA system with variable frequency sec will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1336190