Wireless local area network
First Claim
1. Apparatus comprisingmeans responsive to a stream of input data for generating a sequence of coded modulation signal points representing that data, said coded modulation signal points being generated from a code having built-in diversity,means for transmitting the coded modulation signal points to a receiver, with at least the coded modulation signal points which provide said diversity being transmitted using respective different frequencies,means for detecting ones of the coded modulation signal points received by the receiver that are likely to have been subject to strong interference, andmeans for performing soft decision decoding responsive to the received values of said ones of the coded modulation signal points, other than said detected ones of the coded modulation signal points likely to have been subject to strong interference, to form decisions as to the values of the transmitted coded modulation signal points.
1 Assignment
0 Petitions
Accused Products
Abstract
In a wireless local area network, predetermined interference-detection sequences of signal points, known at both the transmitter and receiver, are transmitted over a plurality of hopping frequencies along with a sequence of data signal points taken from a modulated code exhibiting built-in diversity. In the receiver, the extent to which there are errors in the received interference-detection signal points is used as a mechanism for identifying the likely occurrence of strong interference. If there are no, or few, errors, decoding proceeds normally. However, if the number of errors is above a predetermined threshold, it is assumed that the transmitted signal was subjected to significant interference and an erasure is declared. This is used as "side" information by the decoder to improve its ability to accurately recover data in the presence of interference.
-
Citations
14 Claims
-
1. Apparatus comprising
means responsive to a stream of input data for generating a sequence of coded modulation signal points representing that data, said coded modulation signal points being generated from a code having built-in diversity, means for transmitting the coded modulation signal points to a receiver, with at least the coded modulation signal points which provide said diversity being transmitted using respective different frequencies, means for detecting ones of the coded modulation signal points received by the receiver that are likely to have been subject to strong interference, and means for performing soft decision decoding responsive to the received values of said ones of the coded modulation signal points, other than said detected ones of the coded modulation signal points likely to have been subject to strong interference, to form decisions as to the values of the transmitted coded modulation signal points.
-
8. A method comprising the steps of
generating a sequence of coded modulation signal points representing a stream of input data, said coded modulation signal points being generated from a code having built-in diversity, transmitting the coded modulation signal points to a receiver, with at least the coded modulation signal points which provide said diversity being transmitted using respective different frequencies, detecting ones of the coded modulation signal points received by the receiver that are likely to have been subject to strong interference, and performing soft decision decoding responsive to the received values of said ones of the coded modulation signal points, other than said detected ones of the coded modulation signal points likely to have been subject to strong interference, to form decisions as to the values of the transmitted coded modulation signal points.
Specification