Abstract: Systems, methods, and devices for communicating packets having a plurality of types are described herein. In some aspects, the packets include a compressed MAC header. In some aspects the packets include an acknowledgment (ACK) frame. The fields included in a particular packet type may be based on the type of information to be communicated to the receiving device.

Abstract: Systems, methods, and devices for communicating packets having a plurality of types are described herein. In some aspects, the packets include a compressed MAC header. In some aspects the packets include an acknowledgment (ACK) frame. The fields included in a particular packet type may be based on the type of information to be communicated to the receiving device.

Abstract: Systems, methods, and devices for communicating packets having a plurality of types are described herein. In some aspects, the packets include a compressed MAC header. In some aspects the packets include an acknowledgment (ACK) frame. The fields included in a particular packet type may be based on the type of information to be communicated to the receiving device.

Abstract: A MIMO receiver is provided with a preprocessor for performing QR decomposition of a channel matrix H wherein the factored reduced matrix R is used in place of H and Q*y is used in place of the received vector y in a maximum likelihood detector (“MLD”). The maximum likelihood detector might be a hard-decision MLD or a soft-decision MLD. A savings of computational complexity can be used to provide comparable results more quickly, using less circuitry, and/or requiring less consumed energy, or performance can be improved for a fixed amount of time, circuitry and/or energy. Where the MLD uses approximations, such as finite resolution calculations (fixed point or the like) or L1 Norm approximations, the reduced number of operations resulting from using the reduced matrix results in improved approximations as a result of the finite resolution operations. Other methods of reducing the channel matrix might be used for suitable and/or cumulative advantages.

Abstract: A MIMO receiver is provided with a preprocessor for performing QR decomposition of a channel matrix H wherein the factored reduced matrix R is used in place of H and Q*y is used in place of the received vector y in a maximum likelihood detector (“MLD”). The maximum likelihood detector might be a hard-decision MLD or a soft-decision MLD. A savings of computational complexity can be used to provide comparable results more quickly, using less circuitry, and/or requiring less consumed energy, or performance can be improved for a fixed amount of time, circuitry and/or energy. Where the MLD uses approximations, such as finite resolution calculations (fixed point or the like) or L1 Norm approximations, the reduced number of operations resulting from using the reduced matrix results in improved approximations as a result of the finite resolution operations. Other methods of reducing the channel matrix might be used for suitable and/or cumulative advantages.

Abstract: A soft symbol decoder for use in a multiple input multiple output (MIMO) and OFDM (orthogonal frequency division multiplexing) system. The decoder generates soft symbol values for a digital signal that represents a number of source bits. The source bits are transmitted as symbols in corresponding to points in a signaling constellation. Soft metrics are determined by searching for all possible multi-dimensional symbols that could have been transmitted. The method includes transmitting a sample of the multi-dimensional symbol using K transmit antennas. The multi-dimensional symbol is represent-able as a complex, K-dimensional vector x. Each vector component of vector x represents a signal transmitted with one of the K transmit antennas. After transmission through a communication channel, a sample corresponding to the transmitted sample is received. The received sample is represented by a complex, N-dimensional vector y, where N is the number of receive antennas in the MIMO system.

Abstract: A decoder generates distance and label metrics associated with each label of a coset transmitted in a multi-input multi-output communication system having Mt transmit antennas and Mr receive antennas by performing 2(“u+n”)(Mt?1) searches, where n is the number of encoded bits used to identify one of 2u cosets at the transmitting end and u is the number of unencoded bits used to select one of 2u labels at the transmitting end. The decoder forms an intermediate vector quantity associated with one of the transmit antennas to compute the metrics associated with each of the remaining transmit antennas. The decoder then forms a second intermediate vector quantity to compute the metrics associated with the transmit antenna that was used to form the first intermediate variable. The metrics so computed are used by a Viterbi decoder to identify the coset and the most likely transmitted label in that coset.

Abstract: A communication system with a plurality of access points (AP1, AP2, AP3) and at least one network station (5, 6), the network station (5, 6) being arranged to communicate with one of said the plurality of access points (AP1, AP2, AP3) through a wireless communication protocol, each access point (AP1, AP2, AP3) is able to monitor its access point traffic load and transmit an access point traffic load parameter (ATT) to the network station (5, 6), and the network station (5, 6) is able to monitor its network station traffic load; store a network station traffic load parameter (AUTT); receive access point traffic load parameters (ATT) from the access points (AP1, AP2, AP3); and select a communication connection with one of the access points (AP1, AP2, AP3) using a predetermined cost function taking the access point traffic load parameters (ATT) and the network station traffic load parameters (AUTT) into account.

Abstract: The invention relates to a wireless radiofrequency data communication system comprising: a base-station comprising a multiple of N first groups and a signal processing-unit comprising memory means and processing means, wherein each first group comprises a receiver-unit provided with a receiver and at least one antenna which is connected to the receiver-unit, wherein the signal processing-unit is connected with each of the first groups for processing receive-signals generated by each of the first groups, and a multiple of M second groups for transmitting radiofrequency signals to the first groups, wherein each second group comprises a transmitter-unit provided with a transmitter and at least one antenna which is connected to the transmitter-unit, wherein the memory means of the signal processing-unit is provided with means comprising information about the transfer-functions of radiofrequency signals from each of the antennas of the second groups to each of the antennas of the first groups, and wherein the tran

Abstract: The invention relates to a wireless radiofrequency data communication system comprising: a base-station comprising a multiple of N first groups and a signal processing-unit comprising memory means and processing means, wherein each first group comprises a receiver-unit provided with a receiver and at least one antenna which is connected to the receiver-unit, wherein the signal processing-unit is connected with each of the first groups for processing receive-signals generated by each of the first groups, and a multiple of M second groups for transmitting radiofrequency signals to the first groups, wherein each second group comprises a transmitter-unit provided with a transmitter and at least one antenna which is connected to the transmitter-unit, wherein the memory means of the signal processing-unit is provided with means comprising information about the transfer-functions of radiofrequency signals from each of the antennas of the second groups to each of the antennas of the first groups, and wherein the tran

Abstract: Methods and systems are provided for transmitting a plurality of information signals in a multiple antenna communication system. One or more information signals are coded using a plurality of coders to generate the plurality of coded information signals and an Inverse Fast Fourier Transformation is performed on each of the plurality of coded information signals to create a corresponding output signal. Each of the corresponding output signals are transmitted on a different antenna. Each of the plurality of coded information signals can optionally be separated into K signals. On the receiver side, a signal comprising K different frequencies is received on at least N receive antennas and a Fast Fourier Transformation is applied to each of the at least N received versions of the signal comprising K different frequencies to generate N*K low frequency signals.

Abstract: In a packet detector, one or more tests are performed for packet detection according to packet detection parameters associated with the one or more tests, a rate of false detection is measured, and the packet detection parameters are adjusted accordingly to reduce the rate of false detection. The rate of false detection might be determined by analyzing post-detection and processing of a signal deemed to be a signal representing a packet for a failure of decoding indicative of a false detection. Such analysis might include testing for a failed SFD search, training symbol anomalies, poor conditioning of metrics used to determine frequency offset and OFDM timing, incorrect data fields, or the like.

Abstract: A packet detector joint detects 802.11a packets, 802.11b packets and interference that is within a monitored frequency range but is not formatted as 802.11a packets or 802.11b packets. The packet detector can use signals from one or more antennas. Detection of signals is done using differentially detected correlations. In addition to packet detection, the packet detector can identify signal levels, noise levels and locations of narrowband interference. The process of packet detection and identifying other indicators can be done simultaneously and as the signal is being received.

Abstract: An ATM switching arrangement in which two types of cells are distinguished. A first type of cells is marked as low loss cells and a second type of cells is marked as low delay cells. In the switching arrangement a cell buffer (9) is subdivided into a first memory area (LL) for the low loss cells and a second area (LD) for the low delay cells. In the case of the cell buffer (9) being completely filled, low loss cells get read-in priority over low delay cells. In reading out from the cell buffer low delay cells take priority over low loss cells, unless the low delay area is empty. It is also possible to set a threshold value for the content of the low loss area; when the content of the low loss area exceeds the threshold value outputting of the low loss cells can then be started.