Abstract:
A method and apparatus for channel coding and rate matching of the Physical Uplink Control Channel (PUCCH) and the Physical Downlink Control Channel (PDCCH) is disclosed that uses convolutional encoding to code the control channels. Rate matching is performed using a circular buffer based rate matching algorithm. A rate matching module may contain a single interleaver or may alternatively comprise a plurality of sub-block interleavers. Interleaved coded bits may be stored in the circular buffer in an interlaced format, or output streams from separate sub-block interleavers may be stored contiguously. When a plurality of sub-block interleavers are used, different interleaving patterns may be used. Rate matching may use bit puncturing or repetition to match the rate of the available physical channel resource. Rate matched output bits may be interleaved using a channel interleaver.
Abstract:
The present invention is related to an enhanced equalizer using channel estimation. A scaled version of a channel estimate is used as an expected average behavior of the product of a transmitted signal and a received signal to implement Griffith algorithm. The present invention also uses advance or prediction of a channel estimate to overcome the lag problem inherent in a least means square (LMS) algorithm in a time varying channel. Therefore, the present invention enables the use of a small step size while attaining the same tracking capability with a large step size. A channel estimate at some time in the future is used for updating equalizer filter tap coefficients. This may be performed with a prediction filter. Alternatively, a delay may be introduced in the input data to the filter tap coefficient generator, which makes a channel estimate look like a prediction to the filter tap coefficient generator.
Abstract:
A channel estimation apparatus and method is provided for a wireless communication signal received from at least one relatively mobile wireless transmit/receive unit (WTRU). Predetermined filter coefficients having unique index values are stored in a memory device. An index generator matches estimation values of the mobile unit speed and SNR to a particular filter coefficient, and selects a corresponding index value, whereby the memory performs a look up function according to the index value and outputs a filter coefficient vector. The channel estimation of the wireless communication signal is taken from the output of the filter. Alternatively, a set of parallel filters which run continuously are used to produce several channel estimates, from which the final estimate is selected based on the associated lowest mean square error or highest SNR.
Abstract:
A method for embedding location information in a content object created on a content creation device begins by obtaining location information relating to the current location of the content creation device. The content object is created and the location information is embedded into the content object. A method for displaying location information in connection with a content object begins by selecting a content object to view. The embedded location information is extracted from the selected content object. The location information is interpreted to determine user-friendly location information. The user-friendly location information is displayed with the selected content object.
Abstract:
A system, components and methods provide FEC decoding in a wireless communication system in which signal to noise ratio estimation is used for scaling information captured by a demodulator in processing received wireless communication signals. A preferred wireless transmit receive unit (WTRU) has a channel rate estimation device configured to process the received communication signals for the particular communication channel and to produce channel change rate estimates. A signal to noise ratio (SNR) estimation device of the WTRU is configured to produce SNR estimates based on observation windows of a calculated number of samples of the received signal where the number of samples used for each observation window is calculated a function of the channel change rate estimates produce by the channel rate estimation device.
Abstract:
A method and an apparatus are provided for efficient transmission of low-data-rate packet services in a multiple-input multiple-output (MIMO) mode of operations in the presence of high-data-rate packet services. Precoding weight information (PWI) is signaled implicitly to a wireless transmit receive unit (WTRU). A precoding weight vector is signaled in a high speed shared control channel less (HS-SCCH-less) transmission using a new HS-SCCH type P. This explicit PWI signaling approach transmits the PWI with minimum power overhead. The data carried in the HS-SCCH type P is encoded to minimize the required transmitted power. A channel type HS-SCCH type 2M is also described.
Abstract:
A method and apparatus for encoding channel quality indicator (CQI) and precoding control information (PCI) bits are disclosed. Each of input bits, such as CQI bits and/or PCI bits, has a particular significance. The input bits are encoded with a linear block coding. The input bits are provided with an unequal error protection based on the significance of each input bit. The input bits may be duplicated based on the significance of each input bit and equal protection coding may be performed. A generator matrix for the encoding may be generated by elementary operation of conventional basis sequences to provide more protection to a most significant bit (MSB).
Abstract:
In a wireless communication system, a method and apparatus switches operating modes of a receiver receiving data and operating in a first mode. The method comprises determining whether a criteria is met to switch the operating mode of the receiver. The operating mode of the receiver is switched from the first mode to a second mode if the criteria is met.
Abstract:
A step-size estimator for controlling the step-size of an adaptive equalizer incorporated in a transceiver, (e.g., a wireless transmit/receive unit (WTRU)). The step-size estimator updates at least one adaptive equalizer tap used by the adaptive equalizer based on an apparent speed of a channel established between the transceiver and another transceiver. The step-size estimator includes a speed estimator, a signal-to-noise ratio (SNR) averager and a step-size mapping unit. The speed estimator is used to estimate the apparent speed of the channel, (i.e., the observed and/or measured rate of change of the channel impulse response). The SNR averager generates a common pilot channel (CPICH) SNR estimate. The step-size mapping unit uses the speed estimate and the CPICH SNR estimate to generate a step-size parameter, μ , and a filter taps leakage factor parameter, α , used by the adaptive equalizer to update the filter tap coefficient.
Abstract:
A wireless communication apparatus which uses fast Fourier transforms (FFTs) in an orthogonal frequency division multiplexing (OFDM) receiver which incorporates a beam space antenna array. The beam space antenna array may be implemented with a Butler matrix array. The beam space antenna array may be a circular array, vertical array, or a combination of both circular and vertical arrays, for providing the desired angular antenna coverage. In one embodiment, the antenna array is optimized because the FFTs are linear invariant transform operators, whereby the order of operations in the OFDM receiver can be interchanged.