Apparatus for detecting the presence or the absence of a digitally modulated carrier, a corresponding receiver, and a corresponding method
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Jun 27, 2000
Grant Date -
N/A
app pub date -
Nov 30, 1995
filing date -
Dec 2, 1994
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
The invention relates to apparatus for detecting the presence or the absence of a signal carrier wave received by a receiver. The carrier wave is modulated by a digital signal at a symbol clock frequency. According to the invention, the apparatus includes: a non-linear circuit receiving the received signal or the received signal after it has been frequency transposed, the non-linear circuit supplying in particular a signal whose frequency corresponds to the symbol clock frequency; a narrow-band filter centered on the symbol clock frequency and supplying a filtered signal; detection means for detecting the filtered signal and for supplying a detection signal; and comparator means for comparing the detection signal with a reference value, the output signal from the comparator means constituting a signal indicating the presence or the absence of the carrier wave. The invention is particularly applicable to a receiver including automatic gain control apparatus placed upstream, and the indicator signal may optionally be applied to automatic frequency control apparatus.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Advertisement
Advertisement
Advertisement
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully