Abstract:
Method and receiver for processing a signal in a wireless communication system in which the signal comprises a sequence of chips. The signal is receive data at least one rake finger and sampled. There is a time spacing t1 between successive samples less than the time spacing tc between successive chips in the signal. Channel conditions on the channel are estimated and based on estimated channel conditions by the following steps: monitoring timing of the signal on one of the at least one rake finger to determine a time difference between the timing of the signal on the one of the at least one rake finger and the timing of the generation of the samples, the determined time difference being a multiple of t2, where t2
Abstract:
A method of transmitting an RF signal over a wireless communication network is provided. The method comprises determining a respective weighting factor for each of a plurality of digital signals each corresponding to a respective channel, the weighting factors weighting the digital signals to produce a composite signal intended for transmission as an RF signal via a power amplifier. The method further comprises executing instructions on a processor to dynamically calculate a metric related to the non-linearity of the power amplifier's transfer characteristics for the composite signal using the determined weighting factors. The method further comprises supplying to the power amplifier a signal for transmission as an RF signal and amplifying the signal for transmission at the power amplifier to transmit an RF signal over the wireless communication network via at least one antenna. The method further comprises controlling the transmission based on the metric related to the amplifier non-linearity.
Abstract:
A method, program and apparatus for transmitting from a transmitter to a receiver over a channel using a transmit diversity scheme. The method comprises: receiving power-related information fed back from the receiver to the transmitter; and at the transmitter, using the power-related information to generate channel state information. The method further comprises using the generated channel state information to control for subsequent transmission to the receiver from the multiple transmit antennas of the transmitter.
Abstract:
A method and system for generating channel estimates for processing signals received through first and second transmission channels in a wireless communications network, each channel corresponding to a separate transmit antenna, and each signal comprising a plurality of samples derived from symbols transmitted in the signal by: generating first variable z1 (k) and second variable z2 (k); and providing a set of filter coefficients (I) and generating first and second channel estimates using first and second variables and a set of filter coefficients.
Abstract:
A method, program and user equipment for wireless communication in a cellular communication system comprising a plurality of base stations. The method comprises: synchronizing to one of said the base stations using a synchronization channel transmitted from that base station; receiving a pilot channel from said base station; after synchronizing to said base station, receiving a signal from that base station; and using the pilot channel from said base station to cancel interference on said signal caused by the synchronization channel.
Abstract:
Techniques are provided for a radio link quality monitoring method and apparatus wherein a given user equipment device receives a plurality of Orthogonal Frequency Division Multiplex symbols that comprise a plurality of resource elements distributed in time and frequency, and which include reference symbols. The objective of the radio link quality monitoring is to predict the user equipment detection probability of control messages transmitted by the base station. The radio link quality estimation process calculates two average signal to noise ratio values over the complete frequency bandwidth for two assumed control channel formats corresponding to in-sync and out-of-sync conditions. The results of the calculations are then used to deduce the average error probabilities that are compared with predefined thresholds to provide the in-sync/out-of-sync indications.
Abstract:
Wireless receiver and method of operating a wireless receiver in a wireless communication network for: receiving a signal, the received signal comprising data containing at least one symbol from a symbol alphabet, the symbol alphabet consisting of complex values that define a direction in the complex plane, the received signal further comprising interference; measuring the variance of a first component of the received signal that is perpendicular to the defined direction in the complex plane; estimating the interference power of the received signal using the measured variance of the first component of the received signal; estimating a total power of the received signal; estimating the power of the at least one symbol of the received signal by subtracting the estimated interference power from the estimated total power of the received signal; and based on the estimated interference power and the estimated power of the at least one symbol of the received signal, performing at least one of the steps of: processing the received signal, and generating control information related to the transmission of a further signal from the wireless receiver.
Abstract:
A method and corresponding system for generating an estimate of at least one of a signal power, a noise power and a signal to interference ratio for signal samples received via first and second wireless channels, the signal samples corresponding to pilot symbols transmitted in respective different structures via the first and second wireless channels. The method comprises: calculating first and second variables, each variable being a sequence of values computed from the received signal samples and the pilot symbols for each respective first and second wireless channel; generating first and second channel estimates from the first and second variables; combining the first and second channel estimates to generate a combined channel estimate; and generating at least one of the signal power, noise power and SIR using the combined channel estimate.
Abstract:
The invention describes a method for predicting the performance of the MLD receiver in MIMO channels. The method is based on the iterative principle where the performance of the MLD decoder is derived from that of an iterative receiver architecture with similar performance. The described Iterative MIMO Effective SNR (IMES) technique maps the performance of each MIMO channel realization into a set of effective SNR values for the different streams. This set of effective SNR values can then be used to provide link adaptation feedback to the transmitter so that the most suitable transmission format can be selected according to the characteristics of the propagation channel. Alternatively, this information can be used to adapt the receiver processing to the channel conditions, thereby making it possible, for example, to reduce the receiver power consumption in good signal conditions.
Abstract:
The invention describes a method for predicting the performance of the MLD receiver in MIMO channels. The method is based on the iterative principle where the performance of the MLD decoder is derived from that of an iterative receiver architecture with similar performance. The described Iterative MIMO Effective SNR (IMES) technique maps the performance of each MIMO channel realization into a set of effective SNR values for the different streams. This set of effective SNR values can then be used to provide link adaptation feedback to the transmitter so that the most suitable transmission format can be selected according to the characteristics of the propagation channel. Alternatively, this information can be used to adapt the receiver processing to the channel conditions, thereby making it possible, for example, to reduce the receiver power consumption in good signal conditions.