Method and apparatus for dynamic bandwidth provisioning in frequency division duplex systems

摘要

A method and apparatus are described that provides flexible spectrum usage by using a paired frequency division duplex (FDD) spectrum to enable dynamic access in television white space (TVWS), sub-leased spectrum or unlicensed spectrum, (e.g., industrial, scientific and medical (ISM) bands), in a femto cell environment or the like. Elastic FDD (E-FDD) enables femto cell operation in TVWS, sub-leased spectrum and/or unlicensed spectrum, either simultaneously with licensed spectrum or as an alternate channel to licensed spectrum. E-FDD enables dynamic asymmetric bandwidth allocation for uplink (UL) and downlink (DL) in FDD, and enables variable duplex spacing, (i.e., using FDD with minimum duplex spacing between DL and UL spectrum, or, using hybrid-FDD, (FDD in a time duplexed fashion), when a spectrum gap between the UL and DL spectrum is below a certain minimum threshold. Additionally, the signaling enhancements to implement E-FDD are also provided.

主权项

1. A method of implementing frequency division duplex (FDD), the method comprising:
assessing spectrum usage for uplink (UL) and downlink (DL) based on spectrum usage information, wherein the spectrum usage information includes quality of service requirements; determining availability of spectrum based on sensing; detecting a presence of a primary user on an available whitespace spectrum on a condition that the primary user is using a previously available whitespace spectrum; dynamically allocating the UL spectrum and the DL spectrum from the spectrum around a transmission by the primary user in a previously available unlicensed spectrum in view of spectrum usage assessment and spectrum availability with a variable spacing between the UL spectrum and the DL spectrum; and maintaining communication between a base station and at least one wireless transmit/receive unit by avoiding interference with the transmission by the primary user.