摘要:
Systems and methods are provided for the transmission of waveforms. The method includes inserting at least one TDM pilot symbol located at a transition between wide area and local area waveforms to facilitate decoding of the transmission block.
摘要:
Systems and methodologies are described that facilitate monitoring RF channels in a wireless communication environment to determine whether one or more channels comprise a forward-link-only (FLO) signal. A receiver can receive a first RF channel with a FLO signal and can monitor other RF channels for FLO signals. Upon a determination that a monitored RF channel comprises a FLO signal, the receiver can switch between the first RF channel and the monitored RF channel to facilitate providing seamless reception of the FLO signal, which can be superframe synchronized between RF channels. FLO signal detection can be performed using one or more of a wide-area identification channel energy detection protocol and a wide-area overhead information symbol decoding error detection protocol.
摘要:
Methods and apparatus for adapting a channel estimation scheme in a transceiver in a communication system are disclosed to adapt channel estimation to the transceiver environment, particularly for high Doppler environments. The disclosed methods and apparatus effect determination of an estimate of a power delay profile of a channel or a time correlation of the channel, or both. A channel estimation scheme is then determined based on at least one of the determined power delay profile and time correlation of the channel. By basing determination of a channel estimation scheme on the power delay profile and/or the time correlation of the channel, the channel estimation scheme is adapted to the particular environment of the transceiver by accounting for the delay spread of the channel and/or the speed of the transceiver.
摘要:
Methods and apparatus for RF channel switching in a multi-frequency network. In an aspect, a method includes identifying a local area operations infrastructure (LOI) in the multi-frequency network, generating a channel description message that associates at least one descrambling sequence identifier with each RF channel associated with the LOI, respectively, and distributing the CDM over the LOI. In another aspect, a method includes receiving a CDM that associates at least one descrambling sequence identifier with each RF channel available in a LOI, detecting an RF channel switch event that identifies a selected RF channel, determining a selected descrambling sequence identifier from the CDM based on the selected RF channel, switching to the selected RF channel wherein the selected descrambling sequence identifier identifies a selected descrambling sequence to descramble desired content carried on the selected RF channel, and acquiring the desired content on the selected RF channel.
摘要:
Methods and apparatus for service acquisition in a multi-frequency network. In an aspect, a method is provided for service acquisition in a multi-frequency network. The method includes detecting a service acquisition trigger event and identifying a selected RF channel from an acquisition RF list based on signal strength, wherein the acquisition RF list identifies RF channels in one or more local operations infrastructures (LOIs) of the multi-frequency network. The method also includes acquiring a wide system on the selected RF channel, removing the selected RF channel from the acquisition RF list if the wide system can not be acquired on the selected RF channel, and repeating said operations of identifying, acquiring and removing until the wide system is acquired on the selected RF channel or a system acquisition timeout occurs.
摘要:
Methods and apparatus for timing synchronization based on transitional pilot symbols. In an aspect, a method is provided for time tracking synchronization in an OFDM system. The method includes receiving at least one TDM pilot symbol comprising a plurality of modulated sub-carriers that are configured to provide a channel estimate having a length that extends up to a duration of an FFT used for data transmission. The method also includes determining one or both of an instantaneous and averaged channel estimates from the plurality of modulated sub-carriers, and calculating a timing offset based on one or both of the channel estimates. An apparatus includes a receiver configured to receive the at least one TDM pilot symbol, a channel estimator configured to determine the instantaneous and averaged channel estimates, and a time synchronizer configured to calculate a timing offset based on the channel estimates.
摘要:
Methods and apparatus for time tracking using assistance from TDM pilots in a communication network. In an aspect, a method is provided for time tracking in a device operating on a communication network, wherein the device performs a time tracking algorithm. The method includes determining a delay spread, and modifying at least one parameter used by the time tracking algorithm based on the delay spread. In another aspect, an apparatus is provided for time tracking in a device operating on a communication network, wherein the device performs a time tracking algorithm. The apparatus includes computation logic for determining a delay spread, and control logic for modifying at least one parameter used by the time tracking algorithm based on the delay spread.
摘要:
Pilot transmission and channel estimation techniques for an OFDM system with excess delay spread are described. To mitigate the deleterious effects of excess delay spread, time filtering is utilized. Time filtering is utilized to combat excess delay spread effects in channel estimation. The time filtering is performed in the presence of staggered pilots and helps in improving the channel estimate in the presence of excess delay spread.
摘要:
Methods and apparatus for RF handoff in a multi-frequency network. A method includes generating seamless and partially seamless handoff tables for multiplexes carried in a current LOI, wherein the seamless and partially seamless handoff tables comprise neighboring RF channels carrying one or more of the multiplexes in the current LOI, detecting a handoff event initiated by acquisition failures on a current RF, selecting a selected RF channel from the seamless and partially seamless handoff tables, and performing a handoff to the selected RF channel. An apparatus includes processing logic configured to generate the seamless and partially seamless handoff tables, detect a handoff event initiated by acquisition failures on a current RF, and select a selected RF channel from the seamless and partially seamless handoff tables. The apparatus also includes channel switch logic configured to perform a handoff to the selected RF channel.
摘要:
A new channel is added to FLO networks that carries embedded signaling parameter information. The design is such that regardless of the actual values of the signaling parameters conveyed, a receiver will be able to demodulate this new channel. Moreover, the addition of the new channel does not render a FLO network that has been so configured to not be backwards-compatible with existing devices.