摘要:
Methods and apparatus for correcting frequency errors between a carrier frequency of a signal received by a wireless device and a reference frequency local to the device. For certain aspects, such a method generally includes receiving a signal in a receiver having an LO producing a reference frequency, a radio frequency (RF) phase-locked loop (PLL), and a digital rotator, estimating a frequency difference between a carrier frequency of the received signal and the LO reference frequency, and applying the estimated frequency difference to the RF PLL and the digital rotator.
摘要:
Providing for reduced complexity or improved accuracy in de-mapping received wireless data streams for multi-channel wireless communication is described herein. By way of example, a low-complexity likelihood algorithm can be employed to de-map data bits from the wireless data streams. In one particular example, the likelihood algorithm can approximate a received bit with a subset of received wireless symbols correlated the bit, reducing algorithm complexity. In other examples, a limited set of received wireless symbols can be employed for the subset, further reducing algorithm complexity. According to at least one other example, logarithmic terms of the algorithm can be approximated with non-logarithmic functions, such as a look-up table, series expansion, polynomial approximation, or the like. These approximations can enhance symbol de-mapping accuracy while maintaining or improving processing overhead for a wireless receiver.
摘要:
Providing for reduced complexity or improved accuracy in de-mapping received wireless data streams for multi-channel wireless communication is described herein. By way of example, a low-complexity likelihood algorithm can be employed to de-map data bits from the wireless data streams. In one particular example, the likelihood algorithm can approximate a received bit with a subset of received wireless symbols correlated the bit, reducing algorithm complexity. In other examples, a limited set of received wireless symbols can be employed for the subset, further reducing algorithm complexity. According to at least one other example, logarithmic terms of the algorithm can be approximated with non-logarithmic functions, such as a look-up table, series expansion, polynomial approximation, or the like. These approximations can enhance symbol de-mapping accuracy while maintaining or improving processing overhead for a wireless receiver.
摘要:
Methods and apparatus for correcting frequency errors between a carrier frequency of a signal received by a wireless device and a reference frequency local to the device. For certain aspects, such a method generally includes receiving a signal in a receiver having an LO producing a reference frequency, a radio frequency (RF) phase-locked loop (PLL), and a digital rotator, estimating a frequency difference between a carrier frequency of the received signal and the LO reference frequency, and applying the estimated frequency difference to the RF PLL and the digital rotator.
摘要:
An apparatus and method for high throughput unified turbo decoding comprising loading data from a first data window; computing a first forward state metric using the data from the first data window; storing the first forward state metric in a memory; computing a first reverse state metric using the data from the first data window; storing the first reverse state metric in the memory; and computing the log likelihood ratio (LLR) of the first forward state metric and the first reverse state metric. In one aspect, the above-mentioned steps are repeated with data from a second data window. In another aspect, extrinsic information for the first data window associated with the unified turbo decoding is computed.
摘要:
An apparatus and method for processing signals are disclosed. The apparatus may include a transceiver configured to receive a first paging signal during a first cycle, a memory, and a processor configured to store the received first paging signal in the memory, to switch the transceiver to an off state after the first paging signal is stored in the memory, to process the stored first paging signal while the transceiver is in the off state, and to determine whether to enter an online mode based on the processing.
摘要:
A novel method and apparatus for improving transmit antenna weight tracking using channel vector element to element correlations in a wireless communication system is disclosed. The present channel autocorrelation tracking technique utilizes the observation that tracking can be improved when a channel gain vector contains correlated elements. In a first embodiment of the autocorrelation tracking technique, the present invention extracts a coarse gradient estimate by utilizing a perturbation vector autocorrelation matrix estimate and a perturbation autocorrelation matrix to update TxAA weight vectors accordingly. In a second embodiment of the channel autocorrelation tracking technique, the present invention extracts a coarse gradient estimate by utilizing eigendecompositions, perturbation vector autocorrelation matrix estimates, and perturbation autocorrelation matrices to update TxAA weight vectors accordingly. In a third embodiment of the channel autocorrelation tracking technique, the present invention reduces the phase change that can occur at receivers.
摘要:
Channels are acquired and/or searched in a frequency division multiple access (FDMA) wireless system. Initially, a signal that includes a block of FDMA channels is received and filtered so as to select a frequency band that includes the block of FDMA channels. The filtered signal is then processed to obtain measures of certain frequency components in the filtered signal, and a power estimate for at least one of the FDMA channels is calculated based on at least one of frequency component measures.
摘要:
Provided is a method and an apparatus for pseudo-random noise (PN) code sequence hopping, in which an output PN code sequence is generated by generating and combining several intermediate PN code sequences, each of the intermediate PN code sequences being generated by a corresponding PN code sequence generator. A base state is stored for each of the plural intermediate PN code sequences, and the number of states to advance the output PN code sequence is identified, the number being greater than one. A transformation function is obtained for each of the plural intermediate PN code sequences, based on the number of states to advance the output PN code sequence, and then the base state for each intermediate PN code sequence is advanced by the number of states to advance the output PN code sequence, by utilizing the transformation function for such intermediate PN code sequence, to obtain a new state for such intermediate PN code sequence. The new state for each intermediate PN code sequence is then loaded into the corresponding PN code sequence generator, and the PN code sequence generators are enabled with the new states.
摘要:
A novel method for PN sequence hopping where a PN sequence generator has been disabled for a predetermined time before a future time slot where the PN sequence generator will be enabled. The method comprises the steps of writing a base state into storage for a first hop only, calculating from the base state a new state advancing a PN sequence to the beginning of the future time slot, loading the new state into the PN sequence generator, and enabling the PN sequence generator. For subsequent hops, the base state is the new state calculated in the previous hop. In a preferred version, the step of calculating a new state comprises multiplying the base state by a Galois Field polynomial; a serial Galois Field multiplier can be used to perform this multiplication. A system embodying the present invention comprises a PN sequence generator, a control processor, and a storage device. At a desired time after storing the base state, the PN sequence generator is disabled for a predetermined time before a future time slot where the PN sequence generator will be enabled. The control processor calculates a new state advancing a PN sequence to the beginning of the future time slot, and loads the new state into the PN sequence generator, which is subsequently enabled. The PN sequence generator writes the new state into the storage device for a first hop only; for subsequent hops, the base state is the new state calculated in the previous hop.