Abstract: A cognitive radio band device uses information gleaned from a database inquiry based on geo-location information in combination with spectrum sensing to determine if cognitive radio channels are available for unlicensed use.

Abstract: A TV band device for indoor applications uses information gleaned from a database inquiry based on geo-location information in combination with spectrum sensing to determine if TV channels are available for unlicensed use.

Abstract: Methods and systems for operating a base station communicating with one or more user terminals in an orthogonal frequency division multiple access (OFDMA) system where the one or more user terminals are configured to insert pilots in up stream bursts every nth symbol on each subcarrier, where n is an integer, are provided. The method includes identifying a needed amount of up stream bandwidth to be allocated to a user terminal; determining the subcarriers and the number of symbols per subcarrier to be allocated to meet the identified need in a burst; allocating, for the user terminal, a set of subcarriers and a number of symbols for each member of the set of subcarriers, wherein sufficient symbols per subcarrier per burst are allocated to allow user terminal to send two or more pilots per subcarrier per burst; and transmitting a message to the user terminal, the message identifying the allocated subcarriers and the number of symbols allocated for each subcarrier.

Abstract: Methods and systems which include identifying a needed amount of US bandwidth to be allocated to a user terminal; determining the subcarriers and the number of symbols per subcarrier to be allocated to meet the identified need in a burst; allocating, for the user terminal, a set of subcarriers and a number of symbols for each member of the set of subcarriers, wherein sufficient symbols per subcarrier per burst are allocated to allow user terminal to send two or more pilots per subcarrier per burst; and transmitting a message to the user terminal, the message identifying the allocated subcarriers and the number of symbols allocated for each subcarrier.