ORTHOGONAL FREQUENCY DIVISION MULTIPLE ACCESS WITH CARRIER SENSE

摘要

A communication system in which an access point and one or more devices communicating through the access point adaptively apply Orthogonal Frequency Division Multiple Access (OFDMA). The access point may assign orthogonal subcarriers to devices as in conventional OFDMA, but the access point senses activity on the subcarriers and selects subcarriers without activity for assignment. In an alternative approach, a device that is configured for OFDMA communication may receive a channel assignment from a device that does not support OFDMA. The OFDMA-capable device may use only a portion of the subcarriers in the assigned channel, which may be communicated to the non-OFDMA device. During the non-OFDMA device may then ignore unused subcarriers in error detection and correction to avoid incorrectly classifying communications as erroneous. Information about OFDMA capabilities, subcarrier assignments and subcarriers in use may be communicated as information elements in network control communications, such as beacons and probe messages.

主权项

1. A method performed on a computing device, the method comprising:
receiving, by the computing device from a second device, an assignment of a set of individual subcarriers, where each of the individual subcarriers in the selected set is not in active use according to signal activity levels detected on the each of the individual subcarriers; sending, by the computing device to the second device, a message communicated wirelessly via a subset of the assigned set of individual subcarriers; sending, by the computing device to the second device, a list that identifies any of the individual subcarriers of the assigned set that are not part of the subset used to send the message; and modifying, by the computing device based on the list, error detection and correction processing of messages received such that a lack of information in the any of the individual subcarriers identified in the list is not interpreted as an error.