Abstract:
A method (200) for precoding a sequence of transmit samples (s(t)) for transmission in a multi-antenna system includes the following steps: driving (201) the sequence of transmit samples (s(t)) through a cascade of memory blocks (H n H H n ) in accordance with a sampling time (t) of the sequence of transmit samples (s(t)) which memory blocks (H n H H n ) are based on the n-th channel estimate (H n ) to provide a series of power coefficient ( x ̃ ( t ) ) at exits of respective memory blocks of the cascade of memory blocks (H n H H n ); filtering (202) the series of power coefficients ( x ̃ ( t ) ) based on a filter function (∑ w i ) to provide a precoded transmit sample (y(t)); and upon estimation of a new channel matrix (H n+1 ), sliding (203) the memory blocks (H n+1 H H n+1 ) in the cascade of memory blocks together with the transmit samples (s(t)) of the sequence of transmit samples (s(t)) in driving direction while keeping the memory blocks (H n H H n ) to multiply the previously introduced transmit samples (s(t)).
Abstract translation:一种用于对多天线系统中的发射样本(s(t))序列进行预编码的方法(200)包括以下步骤:通过级联的(0,1)级联驱动(201)发射样本序列(s(t)) 根据第n个信道估计(Hn),根据第n个信道估计(Hn),发送采样序列(s(t))的采样时间(t),存储块(Hn HHn) (Hn HHn)的级联存储块的出口处的功率系数(x(t)); 基于滤波函数(Σwi)对系列功率系数(x(t))进行滤波(202)以提供预编码的发送采样(y(t)); 并且在估计新的信道矩阵(Hn + 1)时,将存储块级联中的存储块(H n + 1 HH n + 1)与发送样本(s(t))一起滑动(203) 同时保持存储块(Hn HHn)乘以先前引入的发送样本(s(t)),从而在驱动方向上的发送样本序列(s(t))。
Abstract:
A communication system (1) comprising an interference unit (10), at least a first (12), and at least a second antenna unit (13), is provided. The communication system (1) transmits a payload signal (17) to an intended receiver (2). The interference unit (10) comprises an interference generator, for generating at least one interference signal (15), and supply it to the at least one first antenna unit (12). Moreover, the interference generator generates the at least one interference signal (15) so that interference is generated in an interference area around the intended receiver (2). The interference unit (10) moreover comprises an interference remover for generating at least one interference removal signal (16), and supply it to the at least one second antenna unit (13). The interference remover generates the at least one interference removal signal (16), so that the interference generated by the at least one interference signal (15) is cancelled out at the location of the intended receiver (2).
Abstract:
The invention proposes a receiver (311) for being served by a multi antenna transmitter (301) over a downlink (321). The receiver comprises at least one antenna (311a) adapted to receive data from the transmitter over the downlink, an estimation unit adapted to estimate channel state information with respect to the downlink (321), a connection unit adapted to establish a connection with at least one cooperating receiver (312) over a respective communication link (331, 332), and to receive from each cooperating receiver (312) channel state information of a channel (322) between the transmitter (301) and said cooperating receiver (312), a computing unit adapted to compute, from the estimated channel state information and from the received channel state information, a precoder for the downlink (321) between the transmitter (301) and the receiver (311), and a feedback unit adapted to transmit to the transmitter (301) information derived from the computed precoder.
Abstract:
A method (400, 500, 600) for determining a value, J opt , of a precoding parameter, J, for precoding a sequence of transmit samples, s(t), for transmission in a multi-antenna system, the method comprising: obtaining (401) values of an objective function, u(J), based on a transmission period, T T , for transmitting the precoded sequence of transmit samples, s(t), a coherence time, T C , of a channel and a precoding performance function, f(J), and characteristics of a precoding performance function, f(J), the transmission period T T depending on a training period, T TR , for channel estimation, a precoding period, T P , for precoding the sequence of transmit samples, s(t), and the coherence time, T C , of the channel; and applying (402) an optimality criterion to the values of the objective function, u(J), with respect to the precoding parameter, J, in order to obtain the value J opt .
Abstract:
A method comprising, at a mobile station, transmitting a pilot message to a base station in response to determining that no signal has been received at the mobile station within a predetermined time period or that a received signal has been below a predetermined intensity within a predetermined time period, said pilot message comprising a pilot tone sent at reduced bandwidth, and receiving a response from the base station, said response beamsteered towards the receive direction and/or power of the pilot message.
Abstract:
The invention relates to a communication receiver device (100) for receiving at least one input signal having an input signal frequency spectrum. The communication receiver device (100) comprises a decomposer (101) configured to decompose the input signal into a plurality of sub-signals, wherein the plurality of sub-signals are allocated to a plurality of frequency bands covering the input signal frequency spectrum, a detector (103) configured to detect whether a frequency band of the plurality of frequency bands is active by determining whether an activity indicator associated with the sub-signal of the frequency band is larger than an activity threshold value, and a combiner (105) configured to combine the sub-signal of a first active frequency band with the sub-signal of a second active frequency band to obtain an output signal, wherein the first active frequency band and the second active frequency band are neighboring frequency bands.
Abstract:
The invention relates to an apparatus (100) for controlling the transmission of a message from a transmitter (110) to a receiver (120a), wherein the apparatus (100) comprises: a generator (101) configured to generate a plurality of message components on the basis of the message such that for reconstructing the message all of the plurality of message components have to be available; and a selector (103) configured to select on the basis of the spatial position of the receiver (120a) a first subset of a plurality of communication relays (115a-e) and to allocate a respective subset of the plurality of message components to each communication relay of the first subset of the plurality of communication relays (115a-e) for transmitting the respective subset of the plurality of message components from the respective communication relay to the receiver (120a).
Abstract:
The invention relates to a network entity (100) for selecting a communication relay (101a) from a plurality of communication relays (100a-c) within the service area (103) of a base station (105) covering a plurality of geographic positions, wherein each communication relay (101a-c) is able to retransmit the communication between the base station (105) and a user equipment (107), wherein the network entity (100) comprises a divider (109) configured to divide the service area (103) into a plurality of different regions on the basis of an attenuation measure at each geographic position of the service area (103), a determiner (111) configured to determine for each pair of regions in the service area (103) a spatial isolation measure on the basis of the attenuation measures at the geographic positions within the regions, and a selector (113) configured to select a communication relay (101a) from the plurality of communication relays (101a-c) on the basis of the spatial isolation measures associated with the geographic position of each communication relay of the plurality of communication relays (101a-c).
Abstract:
The invention proposes a receiver comprising R 0 receiving antenna(s) for receiving data over a downlink from T 0 ≥2 transmitting antennas of a transmitter, a connection unit for a connection with a first list of potentially cooperating receivers that respectively comprise R PCDL(i) receiving antenna(s) for receiving data from T PCDL(i) ≥2 transmitting antennas of a transmitter, i being an index of the first list, and a computing unit for selecting a second list of cooperating receivers by recursively selecting the potentially cooperating receiver at index i=c, adding it to the second list if formula (I) and incrementing c, j being an index of the second list, R CDL(j) the number of receiving antenna(s) of the cooperating receiver at index j and T CDL(j) the number of transmitting antennas of its transmitter. The computing unit computes a precoder for the downlink based on the second list.
Abstract:
A communication device (10) adapted for receiving a MIMO signal is provided. The device comprises a first detector (11) adapted to perform a first symbol detection on the MIMO signal using a first detection method, a detection error determination unit (12) adapted to determine a first detection error of the first symbol detection, a detection error judging unit (13) adapted to determine if the first detection error is above or below a detection threshold, and a second detector (14), adapted to perform a second symbol detection on the MIMO signal using a second detection method, if the detection error judging unit (13) has determined that the first detection error is above the detection threshold. The communication device (10) is adapted to use results of the symbol detection as final symbol detection results, if the detection error judging unit (13) has determined that the first detection error is below the detection threshold.