The present invention relates to a method in which a user equipment receives a downlink signal from a base station in a wireless communication system that supports downlink mimo transmission according to one embodiment of the present invention comprises: receiving downlink control information that includes information indicative of the number of layers (n, 1n8) where one or two enabled code words of the downlink mimo transmission are mapped; on the basis of the downlink control information, receiving downlink data transmitted over the respective n layers and a ue-specific reference signal for each of the n layers; and decoding the downlink data on the basis of the ue-specific reference signals, wherein the information indicative of the number of layers can further include information on a code for identifying the ue-specific reference signals.

A device and method in which a plurality of Zadoff-Chu sequences is allocated to a frame, a value of a parameter in the Zadoff-Chu sequence is different among the plurality of Zadoff-Chu sequences, and the Zadoff-Chu sequence allocated to the frame is different among a plurality of cells.

A device and method is which plurality of Zadoff-Chu sequences is allocated to a frame, a value of a parameter in the Zadoff-Chu sequence is different among the plurality of Zadoff-Chu sequences, and the Zadoff-Chu sequence allocated to the frame is different among a plurality of cells.

A radio frequency (RF) communications system may include a first RF node that transmits data, including a new frequency of operation, and a sequence of pilot symbols spread with a complex spreading code sequence. A second RF node may receive an incoming signal from the first RF node and perform despreading for N sample offset delays to generate N despreading sequences for the sequence of pilot symbols. The second RF node may perform a cross-correlation to select a desired despreading sequence from the N despreading sequences, determine a phase offset and timing offset, process the incoming signal based upon the desired despreading sequence, phase offset and timing offset, and switch to the new frequency of operation.

A radio base station, user equipment (UE), and method of control signaling in wireless communication systems. Control information is transferred from a base station to at least one UE, via a plurality of common pilot channels. A set of unique pilot sequences is predefined, and the base station assigns specific pilot sequences from the set of pilot sequences to specific common pilot channels, forming a pilot sequence assignment pattern representing specific control information. The UE, having knowledge of the relations between pilot sequence assignment patterns and control information, interprets the received pilot sequence assignment pattern as specific control information. The method is particularly well suited for broadcast type control information.

A transmission apparatus maps a first stream of input data to first complex symbols in serial format and convert them into first complex symbols in parallel format. They are inverse Fourier transformed into OFDM signals associated with multiple subcarriers that are transmitted via a first antenna over the multiple subcarriers in a same frequency band over a same time period that includes a same set of time slots. First pilot information is transmitted via a first antenna on a first one of a plurality of pilot subcarriers during the same set of time slots, and second pilot information is sent via a first antenna on a second one of a plurality of pilot subcarriers during the same set of time slots. The second pilot information is different from the first pilot information. A second stream of input data is similarly transformed to form second OFDM signals transmit via a second antenna over the multiple subcarriers in the same frequency band over the same time period that includes the same set of time slots. The first pilot information is transmitted via the second antenna on the second pilot subcarrier during the set of same time slots, and the second pilot information is transmitted on one of the pilot subcarriers during the same set of time slots.

Network node and method in a network node, comprising: grouping a plurality of UEs into at least a first UE group and a second UE group; assigning a mutually orthogonal pilot sequence to each UE comprised in the first UE group; assigning a mutually orthogonal pilot sequence to each UE comprised in the second UE group; assigning a resource-offset to the UEs comprised in each UE group, by which each UE is allowed to start its transmission sub-frame in its Transmission Time Interval, TTI; and transmitting the assigned pilot sequences and the assigned resource-offset to UEs.

A radio frequency (RF) communications system may include a first RF node that transmits data, including a new frequency of operation, and a sequence of pilot symbols spread with a complex spreading code sequence. A second RF node may receive an incoming signal from the first RF node and perform despreading for N sample offset delays to generate N despreading sequences for the sequence of pilot symbols. The second RF node may perform a cross-correlation to select a desired despreading sequence from the N despreading sequences, determine a phase offset and timing offset, process the incoming signal based upon the desired despreading sequence, phase offset and timing offset, and switch to the new frequency of operation.

Systems, methods and apparatus for an optimal achievable performance criterion for a wireless communication system. A method may include determining a joint average channel characteristic for each diversity branch of a plurality of diversity branches. The method may further include determining an optimal size of a first subset of the plurality of diversity branches based on the joint average channel characteristics. The method may further include determining an optimal choice for the first subset based on the joint average channel characteristics. The method may further include determining a number of pilot transmissions required based on the optimal choice of diversity branches for the first subset. The method may further include determining a second subset of the plurality of diversity branches based on instantaneous channel state information.

Systems and methodologies are described that facilitate efficient cell acquisition in a wireless communication system. In one aspect, a reference signal for use in cell acquisition can be constructed in a bandwidth-agnostic manner such that it contains a common central portion in a predetermined frequency band that is independent of a bandwidth utilized by an associated wireless communication system. The central portion can be constructed as a two-dimensional block in time and frequency that spans a default cell search bandwidth, a predetermined bandwidth specified by synchronization codes or other signals, or another suitable bandwidth. A reference signal can then be constructed form the central portion by tiling or expanding the central portion such that it spans the entire system bandwidth.