Abstract: A method is provided of a wireless communication device operating in connection with a cellular communication system providing a serving cell and one or more interfering cells. A signal is received comprising symbols of the serving cell transmitted in a downlink channel and symbols of the one or more interfering cells and a first function of a signal-to-interference ratio of the received signal is calculated. One or more of the interfering cells are selected as dominant interfering cells based on a respective average power of reference symbols of the one or more interfering cells in the received signal, an average power of demodulated symbols of the serving cell in the received signal and a respective average power of demodulated symbols of each of the dominant interfering cells in the received signal are determined.

Abstract: A method is provided of a wireless communication device operating in connection with a cellular communication system providing a serving cell and one or more interfering cells. A signal is received comprising symbols of the serving cell transmitted in a downlink channel and symbols of the one or more interfering cells and a first function of a signal-to-interference ratio of the received signal is calculated. One or more of the interfering cells are selected as dominant interfering cells based on a respective average power of reference symbols of the one or more interfering cells in the received signal, an average power of demodulated symbols of the serving cell in the received signal and a respective average power of demodulated symbols of each of the dominant interfering cells in the received signal are determined.

Abstract: There is provided presence detection of a second transmit antenna port in a distributed antenna port system. Cell-specific reference signals, CRS, are received on a first receive antenna port and a second receive antenna port. The CRS have been transmitted by a first transmit antenna port and a second transmit antenna port in the distributed antenna port system. Reference signal received power, RSRP, measurements and reference signal resource element received power, RSRERP, measurements are estimated from the CRS. Presence is detected by comparing each one of at least one metric based on filtered RSRP measurements and filtered RSRERP measurements to a respective threshold.

Abstract: Techniques for processing a received multi-code code-division multiple-access (CDMA) signal to detect unused spreading codes are disclosed. An example method includes, for each of a plurality of observation time intervals and for each of one or more candidate spreading codes, determining a detection threshold for use in detecting whether the candidate spreading code is unused in the received multi-code CDMA signal, based on a target detection sensitivity and at least one of an estimate of received signal quality and an estimate of channel estimation quality. Estimated signal power for the candidate spreading code is compared to estimated noise and interference power corresponding to a spreading code that is known to be unused or corresponding to a spreading code that carries known symbol values, using the calculated detection threshold. Whether or not the candidate spreading code is unused is then determined, based on the comparison.

Abstract: The invention relates to a method 20 performed in a user equipment 8 for estimating interference within a serving cell 5 of a communication system 1. The user equipment 8 is connected to the serving cell 5 and the communication system 1 further comprising one or more neighboring cells 6, 7 to the serving cell 5. The method 20 comprises: receiving 21 neighboring cell reference signals transmitted in at least one of the neighboring cells 6, 7 and serving cell reference signals transmitted in the serving cell 5; and determining 22 a first interference estimate 1SC,iC of interference within the serving cell 5, the first interference estimate taking into account cancellation of interference from the neighboring cell reference signals. The invention also relates to a user equipment, computer program, and computer program product.

Abstract: There is provided presence detection of a second transmit antenna port in a distributed antenna port system. Cell-specific reference signals, CRS, are received on a first receive antenna port and a second receive antenna port. The CRS have been transmitted by a first transmit antenna port and a second transmit antenna port in the distributed antenna port system. Reference signal received power, RSRP, measurements and reference signal resource element received power, RSRERP, measurements are estimated from the CRS. Presence is detected by comparing each one of at least one metric based on filtered RSRP measurements and filtered RSRERP measurements to a respective threshold.

Abstract: There is provided blind code allocation detection. A method performed in a user equipment comprises receiving a downlink interference signal. The downlink interference signal comprises at least two transmission resource units. Metric vectors are formed for the at least two transmission resource units based on symbol estimates in the transmission resource units. Groups of jointly scheduled transmission resource units are detected based on the metric vectors. A corresponding user equipment, computer program and computer program product are also disclosed.

Abstract: When more than two layers are multiplexed in one CDM group, length-4 OCC has to be used across both clusters in one subframe. This means that slot-by-slot channel estimation according to conventional schemes cannot be exploited and Doppler impact cannot be well overcome. By introducing virtual variables and virtual channel samples that are used in processing two time slots in a subframe independently and applying a frequency domain filter based on the virtual variables and then performing postprocessing based on virtual channel samples, slot-by-slot processing is possible to reduce latency and overcome Doppler impact. Code de-spreading of length-4 OCC is no longer processed in time domain, but in frequency domain with two adjacent CDM subgroups. As a result, the frequency domain filtering can start earlier whereby detection latency and processing time for OCC of length longer than 2 is reduced. It can also be used for the length-2 OCC.

Abstract: In one aspect of the teachings herein, a receiver generates an improved estimate of other-cell covariance for the data region of its own-cell signal, by supplementing its pilot-based estimations of the other-cell covariance with supplemental estimations of other-cell covariance that are determined from control symbols transmitted in the control region its own-cell signal and in one or more selected other-cell signals. While the supplemental estimations are derived from the control region, the receiver advantageously fits them against the pilot-based estimations or against received-signal correlations for the data region, and uses the fitted estimations to obtain an improved estimate of other-cell covariance, for use in generating combining weights for equalization processing of the own-cell signal.

Abstract: A Reference Signal Received Power (RSRP) value is produced from a received Orthogonal Frequency Division Multiplexed (OFDM) signal that comprises a plurality of reference symbols located at known sub-carrier frequencies and times within the received OFDM signal. RSRP value production involves, for each hypothesized error state selected from a plurality of different hypothesized error states, ascertaining a corresponding hypothesized RSRP value, and then using the hypothesized RSRP values as a basis for determining a value for use as the produced RSRP value (e.g., by selecting a maximum one of the hypothesized RSRP values as the produced RSRP value). In this technology, each of the hypothesized error states is a hypothesized frequency error paired with a hypothesized timing error and the corresponding hypothesized RSRP value is produced by adjusting one or more measured channel estimates as a function of the hypothesized error state.

Abstract: In one aspect of the teachings herein, a receiver generates an improved estimate of other-cell covariance for the data region of its own-cell signal, by supplementing its pilot-based estimations of the other-cell covariance with supplemental estimations of other-cell covariance that are determined from control symbols transmitted in the control region its own-cell signal and in one or more selected other-cell signals. While the supplemental estimations are derived from the control region, the receiver advantageously fits them against the pilot-based estimations or against received-signal correlations for the data region, and uses the fitted estimations to obtain an improved estimate of other-cell covariance, for use in generating combining weights for equalization processing of the own-cell signal.

Abstract: A method of transmitting communication signals to a plurality of targeted receivers includes transmitting one or more information streams for individual ones of the targeted receivers according to ongoing transmission scheduling, and controlling the ongoing transmission scheduling to reduce the number of impairment contributors that must be considered in received signal processing by scheduled ones of the targeted receivers. In one embodiment the controlling comprises scheduling the targeted receivers to avoid transmissions to more than one targeted receiver at a time. In the same or another embodiment, the controlling comprises at least one of using equal transmit power allocations for one or more information streams, and using fixed transmit power allocations for one or more of the information streams.

Abstract: The method disclosed herein is implemented in a radio receiver to detect an AWGN channel, where the radio receiver comprises a rake receiver. The radio receiver receives signals transmitted via a propagation channel from a transmitter, and determines that the propagation channel is an AWGN channel when a filtered version of a minimum value of a metric is lower than a threshold value. The metric relates to a difference between a normalized measured power profile of the propagation channel and a normalized power template, which normalized power template is dependent on predetermined sampling timing shifts and on rake finger positions within the rake receiver.

Abstract: A receiver and method for receiving and processing a sequence of transmitted symbols in a digital communication system utilizing soft pilot symbols. A set of soft pilot symbols are transmitted with higher reliability than the remaining symbols in the sequence by modulating the soft pilot symbols with a lower order modulation such as BPSK or QPSK while modulating the remaining symbols with a higher order modulation such as 16 QAM or 64 QAM. The receiver knows the modulation type and location (time/frequency/code) of the soft pilot symbols, and demodulates them first. The receiver uses the demodulated soft pilot symbols as known symbols to estimate parameters of the received radio signal. Unlike traditional fixed pilots, the soft pilots still carry some data. Additionally, the soft pilots are particularly helpful in establishing the amplitude reference essential in demodulating the higher order modulation symbols.

Abstract: The method disclosed herein is implemented in a radio receiver to detect an AWGN channel, where the radio receiver comprises a rake receiver. The radio receiver receives signals transmitted via a propagation channel from a transmitter, and determines that the propagation channel is an AWGN channel when a filtered version of a minimum value of a metric is lower than a threshold value. The metric relates to a difference between a normalized measured power profile of the propagation channel and a normalized power template, which normalized power template is dependent on predetermined sampling timing shifts and on rake finger positions within the rake receiver.

Abstract: The invention relates to a method 20 performed in a user equipment 8 for estimating interference within a serving cell 5 of a communication system 1. The user equipment 8 is connected to the serving cell 5 and the communication system 1 further comprising one or more neighboring cells 6, 7 to the serving cell 5. The method 20 comprises: receiving 21 neighboring cell reference signals transmitted in at least one of the neighboring cells 6, 7 and serving cell reference signals transmitted in the serving cell 5; and determining 22 a first interference estimate lsc,ic of interference within the serving cell 5, the first interference estimate taking into account cancellation of interference from the neighboring cell reference signals. The invention also relates to a user equipment, computer program, and computer program product.

Abstract: Techniques for processing a received multi-code code-division multiple-access (CDMA) signal to detect unused spreading codes are disclosed. An example method includes, for each of a plurality of observation time intervals and for each of one or more candidate spreading codes, determining a detection threshold for use in detecting whether the candidate spreading code is unused in the received multi-code CDMA signal, based on a target detection sensitivity and at least one of an estimate of received signal quality and an estimate of channel estimation quality. Estimated signal power for the candidate spreading code is compared to estimated noise and interference power corresponding to a spreading code that is known to be unused or corresponding to a spreading code that carries known symbol values, using the calculated detection threshold. Whether or not the candidate spreading code is unused is then determined, based on the comparison.

Abstract: A Reference Signal Received Power (RSRP) value is produced from a received Orthogonal Frequency Division Multiplexed (OFDM) signal that comprises a plurality of reference symbols located at known sub-carrier frequencies and times within the received OFDM signal. RSRP value production involves, for each hypothesized error state selected from a plurality of different hypothesized error states, ascertaining a corresponding hypothesized RSRP value, and then using the hypothesized RSRP values as a basis for determining a value for use as the produced RSRP value (e.g., by selecting a maximum one of the hypothesized RSRP values as the produced RSRP value). In this technology, each of the hypothesized error states is a hypothesized frequency error paired with a hypothesized timing error and the corresponding hypothesized RSRP value is produced by adjusting one or more measured channel estimates as a function of the hypothesized error state.

Abstract: A multi-carrier linear equalization receiver, e.g., a RAKE receiver or chip equalization receiver, is described herein. The multi-carrier receiver distributes processing delays among a plurality of received carriers based on a dispersion determined for each carrier. The receiver initially allocates a minimum number of processing delays sufficient for light dispersion to each carrier. For the dispersive carriers, the receiver allocates one or more additional processing delays. In one embodiment, the additional processing delays are allocated to the dispersive carriers based on SIR.

Abstract: This disclosure is directed to a wireless receiver and a method for configuring the wireless receiver, comprising the actions of determining a geometry factor for a channel over which signals are transmitted to the wireless receiver, the geometry factor being a measure indicative of inter-cell interference plus noise power at the wireless receiver; determining the variance of the determined geometry factor, the variance being a measure indicative of the variation in time or rate of the geometry factor; and configuring the wireless receiver based on the geometry factor and the variance of the geometry factor.