摘要:
A network entity in a multi-transmit antenna system, such as a transmitting or receiving entity, includes a component such as a pre-coder or a receiver, and is configured for full-spatial-rate coding data. The network entity is capable of providing a full-spatial-rate codebook having been designed by selecting an underlying partial-spatial-rate codebook designed for a system configured for partial-spatial-rate coding data. The full-spatial-rate codebook can then be designed in a manner including defining the full-spatial-rate codewords based upon partial-spatial-rate codewords of the partial-spatial rate codebook and basis vectors of a null space of the respective partial-spatial-rate codewords in a multidimensional vector space. The network entity can also be capable of selecting codewords of the codebook in accordance with a sub-space tracking method whereby the codewords of the codebook can be selected in a manner that exploits correlations therebetween.
摘要:
A network entity in a multi-transmit antenna system, such as a transmitting or receiving entity, includes a component such as a pre-coder or a receiver, and is configured for full-spatial-rate coding data. The network entity is capable of providing a full-spatial-rate codebook having been designed by selecting an underlying partial-spatial-rate codebook designed for a system configured for partial-spatial-rate coding data. The full-spatial-rate codebook can then be designed in a manner including defining the full-spatial-rate codewords based upon partial-spatial-rate codewords of the partial-spatial rate codebook and basis vectors of a null space of the respective partial-spatial-rate codewords in a multidimensional vector space. The network entity can also be capable of selecting codewords of the codebook in accordance with a sub-space tracking method whereby the codewords of the codebook can be selected in a manner that exploits correlations therebetween.
摘要:
A method and apparatus for estimating separate channel frequency responses for two channels in an orthogonal frequency division multiplexing system with two transmitters is disclosed. The channel frequency responses are estimated using specifically selected training symbols that are broadcast from the two transmitters. The training symbols are specifically selected so as to improve the estimation of the channel frequency responses for each channel, while requiring the same amount of training symbols as in an estimation of the channel frequency response of a single channel.
摘要:
Precoding information is provided (implicitly or explicitly) to a particular user equipment UE. Closed-loop spatial coding for a control channel is selected for the particular user equipment, and at least one control channel element CCE is determined within the particular user equipment's search space of the control channel that is associated with the provided precoding information. The determined at least one CCE is spatially encoded using the provided precoding information to schedule radio resources for the particular user equipment. The UE determines a search space for a control channel, and from received radio resource control signaling determines at least one CCE within the search space that is to be encoded with closed-loop spatial coding. The UE decodes the determined at least one CCE within the search space using a closed-loop spatial decoding with precoding information associated with the at least one CCE to find radio resources scheduled for the particular UE.
摘要:
A circuit that includes an input for coupling to a MIMO signal received from a channel to compute a change of basis matrix T and a reduced lattice basis matrix HT, to form a list L of points used for soft decision calculation using columns of the matrix HT and to perform MIMO detection for each point in the list L. The circuit further includes an output to output a list C of constellation points to a unit for use in to calculating soft bit decisions. The list L may include a received point r and a set of points that are formed by adding to the point r a column of the matrix HT multiplied by +1, −1, +i, or −i, or it may be formed by performing hard MIMO detection for the received point r, and adding the columns of HT to the to the hard decision point, or it may be formed by using a hard decision estimate of transmitted vector x and adding multiplied columns of the matrix T to the vector x.
摘要:
A semi-single frequency network (SFN) concept is presented. According to the SFN concept, the same data signal is transmitted from multiple base stations to a mobile terminal simultaneously on the same frequency band. Accordingly, the transmitted signals are combined in the radio channel and the mobile terminal experiences the transmitted signals as one signal propagated through a multipath channel. Additionally, each base station transmits a base station specific pilot signal. The mobile terminal carries out a channel estimation procedure for each received pilot signal and combines the channel estimates to obtain information how to equalize the received data signal. Then, the mobile terminal calculates equalization weights from the combined channel estimates and equalizes the received data signal.
摘要:
Apparatus, and an associated method, for facilitating communication of data upon a communication channel which exhibits fading. Orthogonal transmit diversity techniques and trellis-coded modulation techniques are utilized to form a signal permitting the communication of data at high data rates while maintaining spectral efficiency, good error rate performance, without excessive computational complexity. The apparatus and associated method is advantageously implemented in a WLAN (Wireless Local Area Network) constructed pursuant to the IEEE 802.11 standard.
摘要:
A semi-single frequency network (SFN) concept is presented. According to the SFN concept, the same data signal is transmitted from multiple base stations to a mobile terminal simultaneously on the same frequency band. Accordingly, the transmitted signals are combined in the radio channel and the mobile terminal experiences the transmitted signals as one signal propagated through a multipath channel. Additionally, each base station transmits a base station specific pilot signal. The mobile terminal carries out a channel estimation procedure for each received pilot signal and combines the channel estimates to obtain information how to equalize the received data signal. Then, the mobile terminal calculates equalization weights from the combined channel estimates and equalizes the received data signal.
摘要:
A signal vector is received over a plurality of channels. A channel matrix H is determined that represents at least one of the plurality of channels. An iterative algorithm such as Lenstra-Lenstra-Lovasz is used to determining a change of basis matrix T that when multiplied with the channel matrix H converges to a matrix H*T that is more orthogonal than the channel matrix H. In one aspect the iterative algorithm is upwardly bounded in the number of iterations (e.g., 20 or 30 iterations) that it may perform for any specific channel realization to determine the change of basis matrix T. In another aspect the algorithm is initiated with a matrix derived from a previously determined change of basis matrix. Both aspects may be combined in a single method or device, or either employed separately.
摘要:
A device for block transmission involving a first number of subcarriers (N), comprising: storage means for storing at least one transmission matrix having a dimension equal to the first number. The transmission matrix being arranged so that the columns of the transmission matrix represent a first transmission characteristic and the rows of the transmission matrix represent a second transmission characteristic. The transmission matrix comprises a second number (k) of block submatrices, each submatrix separated by at least one row and/or column from a further submatrix by a null matrix block.