Abstract:
A radio user equipment (UE) mobility status is determined in a communications node. UE mobility status measurements associated with the UE communicating over a radio channel are performed. The UE mobility status corresponds to a degree of variation of the radio channel over time. Channel characteristics of the radio channel at a first time and at a second later time are determined. Based on the determined channel characteristics, a channel characteristic error metric is determined and compared to a predetermined threshold. The UE mobility status is determined based on one or more iterations of the threshold comparison.
Abstract:
A transmission method for simultaneously transmitting a first modulated signal and a second modulated signal at the same frequency includes performing precoding on both signals using a fixed precoding matrix and regularly changing the phase of at least one of the signals. In this method, the power ratio between a plurality of signals transmitted from a plurality of antennas at the same frequency and at the same time differs from the power ratio between a plurality of pilot signals transmitted from the plurality of antennas at the same frequency and at the same time, whereby the accuracy of channel estimation by a reception device is improved.
Abstract:
Methods, apparatus and computer program products are provided for establishing a time-frequency reference signal pattern configuration in a carrier extension or a carrier segment, such as for cell-specific reference signals (CRS) and/or demodulation reference signals (DM RS). One method includes receiving information regarding a time-frequency reference signal pattern configuration in a carrier extension or carrier segment. The time-frequency reference signal pattern configuration defines a subframe to include a reference signal based upon a time density parameter and defines a resource element to be utilized within the subframe based upon a frequency density parameter. This method also includes receiving reference signals pursuant to the time-frequency reference signal pattern configuration such that reference signals have a coherence time Tcoh with at least one subframe including a reference signal in the CE or CS per Tcoh and a coherence bandwidth Bcoh with at least one resource element containing a reference signal per Bcoh.
Abstract:
A method and apparatus for sending and receiving channel quality indicators (CQIs) is disclosed. A CQI may be periodically sent or received. A CQI may also be sent or received upon request by a network.
Abstract:
All data symbols used in data transmission of a modulated signal are precoded by switching between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol along the frequency axis and the time axis all differ. A modulated signal with such data symbols arranged therein is transmitted.
Abstract:
Aspects of the present disclosure describe an efficient channel estimation algorithm for high-speed processing of dedicated reference signals. The channel estimation algorithm may utilize one or more compressed interpolation matrices. The compressed interpolation matrices may be selected based on the Doppler value and signal to noise ratio (SNR) of the channel.
Abstract:
A method for communication includes receiving in a receiver signals, which include one or more dedicated reference signals and are transmitted from a transmitter over a communication channel in multiple blocks. The signals in each block, including the dedicated reference signals, are transmitted on a respective group of subcarriers over a respective time interval and are precoded using a respective precoding scheme that maps the signals onto multiple antenna ports of the transmitter. One or more parameters of the communication channel are estimated over the dedicated reference signals included in two or more of the blocks whose respective precoding schemes do not differ from one another. The signals are decoded based on the estimated parameters.
Abstract:
A method for communication includes receiving in a receiver signals, which include one or more dedicated reference signals, that are transmitted from a transmitter over a communication channel in multiple blocks. The signals in each block, including the dedicated reference signals, are transmitted on a respective group of subcarriers over a respective time interval and are precoded using a respective precoding scheme that maps the signals onto multiple antenna ports of the transmitter. Based on the received signals, feedback is computed in the receiver with respect to the communication channel in each of multiple spectral sub-bands, and the feedback for the multiple spectral sub-bands is reported to the transmitter. One or more parameters of the communication channel are estimated jointly over the dedicated reference signals included in each of the spectral sub-bands for which the feedback is reported. The signals are decoded based on the estimated parameters.
Abstract:
All data symbols used in data transmission of a modulated signal are precoded by switching between precoding matrices so that the precoding matrix used to precode each data symbol and the precoding matrices used to precode data symbols that are adjacent to the data symbol along the frequency axis and the time axis all differ. A modulated signal with such data symbols arranged therein is transmitted.
Abstract:
Embodiments herein relate to a method in a user equipment (10) for performing channel estimation of one or more long term channel properties at the user equipment (10), wherein the user equipment (10) is served by a radio network node (12). The user equipment (10) assumes that a default Channel State Information Reference Signal, CSI-RS, resource is co-located with a Demodulation Reference signal, DMRS, port when co-location is not explicitly signalled from the radio network node (12), wherein the default CSI-RS resource is configured by reading a predetermined entry in a configurable list of candidate co-location CSI-RS resources for a dynamic indication of co-location options in a Downlink Control Information, DCI, format. When assumed to be co-located, the user equipment (10) estimates one or more long term channel properties of the DMRS port and the default CSI-RS resource based on the assumption that the default CSI-RS resource is co-located with the DMRS port.