The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Dec. 09, 2014

Filed:

Feb. 23, 2012
Applicants:

Douglas Cairns, Durham, NC (US);

Elias Jonsson, Malmö, SE;

Inventors:

Douglas Cairns, Durham, NC (US);

Elias Jonsson, Malmö, SE;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04L 27/00 (2006.01); H04L 25/02 (2006.01); H04L 27/227 (2006.01); H04L 27/38 (2006.01); H04L 27/34 (2006.01); H04L 25/06 (2006.01); H04L 25/03 (2006.01); H04L 1/00 (2006.01);
U.S. Cl.
CPC ...
H04L 25/0236 (2013.01); H04L 25/0226 (2013.01); H04B 2201/70701 (2013.01); H04L 2025/0342 (2013.01); H04L 2027/0093 (2013.01); H04L 25/021 (2013.01); H04L 2001/0098 (2013.01); H04L 27/0012 (2013.01); H04L 27/227 (2013.01); H04B 2201/709727 (2013.01); H04L 1/0068 (2013.01); H04L 27/3818 (2013.01); H04L 2025/03796 (2013.01); H04L 27/3455 (2013.01); H04L 2025/03509 (2013.01); H04L 2025/03401 (2013.01); H04L 1/0017 (2013.01); H04L 25/03044 (2013.01); H04L 25/03324 (2013.01); H04L 25/061 (2013.01); H04L 2027/0061 (2013.01); H04L 2025/03426 (2013.01); H04L 1/0041 (2013.01);
Abstract

A receiver and method for receiving and processing a sequence of transmitted symbols in a digital communication system utilizing soft pilot symbols. A set of soft pilot symbols are transmitted with higher reliability than the remaining symbols in the sequence by modulating the soft pilot symbols with a lower order modulation such as BPSK or QPSK while modulating the remaining symbols with a higher order modulation such as 16 QAM or 64 QAM. The receiver knows the modulation type and location (time/frequency/code) of the soft pilot symbols, and demodulates them first. The receiver uses the demodulated soft pilot symbols as known symbols to estimate parameters of the received radio signal. Unlike traditional fixed pilots, the soft pilots still carry some data. Additionally, the soft pilots are particularly helpful in establishing the amplitude reference essential in demodulating the higher order modulation symbols.


Find Patent Forward Citations

Loading…