Abstract: In one embodiment, a network system has a plurality of access points, wherein each access point can be used for wireless communication with at least one station, wherein each access point can (1) receive a probe signal with either a first or second channel frequency and (2) generate and transmit, in response to the probe signal, a response signal with the first or second channel frequency. At least one access point selects at least one channel frequency for the wireless communication with the at least one station on the basis of at least one response signal received with the first channel frequency as transmitted by any of the other access points and/or at least one response signal received with the second channel frequency as transmitted by any of the other access points.

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: MIMO modulation is supported in a wireless network with at least one degenerate node. A transmitter separates data into multiple streams for modulation. To transmit the modulated data, the transmitter uses a separate antenna for each data stream or coherently combines the modulated data streams prior to transmission via fewer antenna than modulated data streams. In either case, the received signal includes a contribution from each data stream. A receiver is configured for processing multiple signals sent in parallel from multiple transmit antennas; thus, the operation of the receiver is unaffected by whether the multiple data streams of the transmitter were combined in the channel after transmission or in whole or part in the transmitter prior to transmission.

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 receiver chain is provided for use in wireless data communication including a plurality of receive antennas and a vector Barker decoder or a CCK decoder. The vector Barker decoder operates on the plurality of received signals, preferably processed through a plurality of channel matched filters. The weightings of the plurality of channels can be done using a slicer variance, a PLL variance or another method.

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 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: A receiver chain is provided for use in wireless data communication including a plurality of receive antennas and a vector Barker decoder or a CCK decoder. The vector Barker decoder operates on the plurality of received signals, preferably processed through a plurality of channel matched filters. The weightings of the plurality of channels can be done using a slicer variance, a PLL variance or another method.

Abstract: Detection of a symbol from a received signal wherein the symbol is a selected symbol out of a predetermined set of symbols, wherein each symbol of the predetermined set is a complementary coded keying (CCK) symbol having a sequence of chips wherein each of the chips is phase shift keying (PSK)-modulated according to a selected modulation code wherein each of the selected modulation codes has a first sub-modulation code which is a selection from a plurality of first sets of predetermined phase modulating elements and a second sub-modulation code which is a selection from one second set of predetermined phase modulating elements wherein at least one of the predetermined phase modulating elements of the second set is a complex value such as defined in the high speed IEEE 802.11b standard, wherein a modulation code is selected from the modulation codes which correlates according to a correlation method with the received signal.

Abstract: The key of the invention is to introduce an interoperability device in a communication system which integrates an IEEE 802.11 transceiver and a Bluetooth transceiver. The device prevents that one transceiver is transmitting while the other is receiving, which would cause interference at the receiving transceiver. In addition, the device preferably prevents that both systems are transmitting at the same time to avoid interference at the receiving device(s). Optionally the device prohibits simultaneous reception of both transceivers. In that way the radio receiver can be shared between the devices, allowing a cheaper and smaller hardware design.

Abstract: The invention relates to a method for the detection of a symbol from a received signal wherein the symbol is a selected symbol out of a predetermined set of symbols, wherein each symbol of the predetermined set is a CCK symbol comprising a sequence of chips wherein each of the chips is PSK-modulated according to a selected modulation code wherein each of the selected modulation codes comprises a first sub-modulation code which is a selection from a plurality of first sets of predetermined phase modulating elements and a second sub-modulation code which is a selection from one second set of predetermined phase modulating elements wherein at least one of said predetermined phase modulating elements of said second set is a complex value such as defined in the high speed IEEE 802.11b standard, wherein a modulation code is selected from said modulation codes which correlates according to a correlation method with the received signal.

Abstract: A network system comprising a plurality of access points, wherein each access point can be used for wireless communication with at least one station, wherein each access point is arranged:

Abstract: The invention relates to a wireless radiofrequency data communication system comprising:

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 plurality of access points (AP1, AP2, AP3) through a wireless communication protocol, each access point (AP1, AP2, AP3) is able to:

Abstract: The invention relates to a wireless radiofrequency data communication system comprising:

Abstract: The key of the invention is to introduce an interoperability device in a communication system which integrates an IEEE 802.11 transceiver and a Bluetooth transceiver. The device prevents that one transceiver is transmitting while the other is receiving, which would cause interference at the receiving transceiver. In addition, the device preferably prevents that both systems are transmitting at the same time to avoid interference at the receiving device(s). Optionally the device prohibits simultaneous reception of both transceivers. In that way the radio receiver can be shared between the devices, allowing a cheaper and smaller hardware design.

Abstract: The present invention teaches a system and method to reduce the peak-to-average power ratio of systems transmitting parallel channels. Examples of such systems are Orthogonal Frequency Division Multiplex (OFDM) and Orthogonal Code Division Multiplex (OCDM), also known as multi-code CDMA. Both systems have the disadvantage of a large peak-to-average power (PAP) ratio, which degrades the efficiency of the power amplifier of the transmitter. The present invention reduces the PAP problem by canceling the large signal peaks through subtraction of an appropriate reference function. That is, a time shifted and scaled reference function is subtracted from the sampled signal, such that each subtracted reference function reduces the peak power of at least one signal sample. In accordance with the present invention, an appropriate reference function with approximately or exactly the same bandwidth as the transmitted signal is selected.

Abstract: The combined complementary encoder and modulation system for an OFDM transmitter system combines complementary coding and modulation and exploits the similarity of their mathematical structure to reduce implementation complexity. In doing so, the improved OFDM transmitter system uses complementary codes to reduce the power-to-average power (PAP) ratio of the transmitted signal. Additionally, the combined complementary encoder and modulation system can be modified to provide scaleablity, which allows a transmitter to operate in various transmission environments. More precisely, scaleability refers to the transmitter's capability to adapt the bit rate of the data, so as to satisfy varying signal bandwidth, delay spreads, tolerance and signal-to-noise ratio requirements.

Abstract: The encoding/transmission of information in an OFDM system is enhanced by using complementary codes. The complementary codes, more particularly, are converted into phase vectors and the resulting phase vectors are then used to modulate respective carrier signals. The modulated result is then transmitted to a receiver which decodes the received signals to recover the encoded information.