Abstract: A multi-user access node for receiving concurrent signals which are carrying redundant chip sequences at a baseband rate, the access node including: a plurality of antennas organized in an antenna configuration; a main transceiver comprising an analog receiver and an ADC for converting an incoming signal into a digital signal which comprises the incoming chip sequences; a switch for switching the transceiver between the plurality of antennas; a controller configured for: initializing the multi-user access node by switching the transceiver between the plurality of antennas to capture a spatial character of the different users based on unique initialization chip sequences from the different users, separating collided chip sequences transmitted by different users by switching the transceiver between the plurality of antennas according to a scrambling sequence and by using the spatial character in combination with the applied scrambling sequence.

Abstract: A communication system comprising: input buffers adapted for buffering incoming data streams of samples from one or more channels; a receiver adapted for sequentially processing data from the input buffers; a processing rate of the receiver is higher than or equal to an incoming data rate of the incoming data; context memory adapted for saving an internal status of the receiver after processing the data corresponding with an input buffer before switching to a next input buffer and for restoring the internal status, wherein the receiver is adapted for processing the incoming data in a frame detection phase, and in a frame demodulation phase in which frames and/or subframes are demodulated into bits and wherein the internal status of the receiver related to an input buffer is only saved and restored in the frame detection phase or before and after demodulating subframes.

Abstract: A multi-user access node for receiving concurrent signals which are carrying redundant chip sequences at a baseband rate, the access node including: a plurality of antennas organized in an antenna configuration; a main transceiver comprising an analog receiver and an ADC for converting an incoming signal into a digital signal which comprises the incoming chip sequences; a switch for switching the transceiver between the plurality of antennas; a controller configured for: initializing the multi-user access node by switching the transceiver between the plurality of antennas to capture a spatial character of the different users based on unique initialization chip sequences from the different users, separating collided chip sequences transmitted by different users by switching the transceiver between the plurality of antennas according to a scrambling sequence and by using the spatial character in combination with the applied scrambling sequence.

Abstract: A communication system comprising: input buffers adapted for buffering incoming data streams of samples from one or more channels; a receiver adapted for sequentially processing data from the input buffers; a processing rate of the receiver is higher than or equal to an incoming data rate of the incoming data; context memory adapted for saving an internal status of the receiver after processing the data corresponding with an input buffer before switching to a next input buffer and for restoring the internal status, wherein the receiver is adapted for processing the incoming data in a frame detection phase, and in a frame demodulation phase in which frames and/or subframes are demodulated into bits and wherein the internal status of the receiver related to an input buffer is only saved and restored in the frame detection phase or before and after demodulating subframes.

Abstract: Apparatus is provided for: storing at least one three-dimensional matrix C[M][N][K] of calibration data; performing singular value decomposition of each at least one three-dimensional matrix C[M][N][K] of calibration data to produce at least one first unitary rotation matrix U, at least one diagonal scaling matrix S and at least one second unitary rotation matrix V; and resizing each of the at least one first unitary rotation matrix U, the at least one diagonal scaling matrix S and the at least one second unitary rotation matrix V by removing dimensions therefrom, thereby producing resized matrices U, S and V. Corresponding decompression is also provided.

Abstract: Apparatus is provided for: storing at least one three-dimensional matrix C[M][N][K] of calibration data; performing singular value decomposition of each at least one three-dimensional matrix C[M][N][K] of calibration data to produce at least one first unitary rotation matrix U, at least one diagonal scaling matrix S and at least one second unitary rotation matrix V; and resizing each of the at least one first unitary rotation matrix U, the at least one diagonal scaling matrix S and the at least one second unitary rotation matrix V by removing dimensions therefrom, thereby producing resized matrices U, S and V. Corresponding decompression is also provided.

Abstract: One of the embodiments of the present invention relates to a method for modulation. The method comprises: providing a first bit sequence of continuous bits “1” or continuous bits “0” generating a second bit sequence by replacing, in each of a plurality of modulation intervals with a predetermined bit number, at least one bit of the first bit sequence at least one fixed position of the respective modulation interval with one information bit from an information bit sequence; and modulating the second bit sequence so as to generate a positioning packet with a modulated continuous wave signal for transmission. The embodiments further relate to a method for demodulation. Embodiments of the present invention also provide corresponding apparatuses and computer program products.

Abstract: Apparatus is provided for: storing at least one three-dimensional matrix C[M][N][K] of calibration data; performing singular value decomposition of each at least one three-dimensional matrix C[M][N][K] of calibration data to produce at least one first unitary rotation matrix U, at least one diagonal scaling matrix S and at least one second unitary rotation matrix V; and resizing each of the at least one first unitary rotation matrix U, the at least one diagonal scaling matrix S and the at least one second unitary rotation matrix V by removing dimensions therefrom, thereby producing resized matrices U, S and V. Corresponding decompression is also provided.

Abstract: Apparatus comprises a memory configured to store a matrix of transmit data; a multi-element antenna; and a transmitter configured to transmit a signal from a multi-element antenna as part of a packet within a transmit period in a switching interval by: switching between different elements of the multi-element antenna in a sequence of transmit intervals within the transmit period; and deriving the signal for transmission in different transmit intervals from different ones of the transmit data in the matrix. Also, apparatus comprises a receiver configured to receive plural packets; and an accumulator configured, for each packet, to accumulate signals received in a switching interval of the packet. The apparatus is configured to: derive a correlation metric for each of the packets from the accumulated signals for the packets; identify a packet with the best correlation metric; identify a direction associated with the packet identified as having the best correlation metric; and provide the direction as an output.

Abstract: Provided are methods, apparatuses, and computer program products for calibrating a direction-finding system in a handheld device. A method is provided, which comprises: displaying instructions for orienting a device such that an image of a calibration source through a camera of the device falls in a designated position on a screen of said device; receiving a signal from said calibration source via an antenna array of the device; calculating an orientation angle between said device and said calibration source based on said image of the calibration source; storing pairs of the signal and the orientation angle at various instances while moving or rotating the device to make the image of the calibration source move along a predefined trajectory displayed on the screen; and calibrating a direction-finding system in the device based on the stored pairs of the signal and the orientation angle.

Abstract: Apparatus is provided for: storing a four-dimensional matrix of fixed point calibration data; rearranging the four-dimensional matrix of fixed point calibration data into a one-dimensional sequence; calculating a differential sequence of the one-dimensional sequence; saving the differential sequence and a first element of the one-dimensional sequence into a binary file; and compressing the binary file using a DEFLATE algorithm. Apparatus is provided for corresponding decompression also.

Abstract: One of the embodiments of the present invention relates to a method for modulation. The method comprises: providing a first bit sequence of continuous bits “1” or continuous bits “0” generating a second bit sequence by replacing, in each of a plurality of modulation intervals with a predetermined bit number, at least one bit of the first bit sequence at at least one fixed position of the respective modulation interval with one information bit from an information bit sequence; and modulating the second bit sequence so as to generate a positioning packet with a modulated continuous wave signal for transmission. The embodiments further relate to a method for demodulation. Embodiments of the present invention also provide corresponding apparatuses and computer program products.

Abstract: Apparatus is provided for: storing a four-dimensional matrix of fixed point calibration data; rearranging the four-dimensional matrix of fixed point calibration data into a one-dimensional sequence; calculating a differential sequence of the one-dimensional sequence; saving the differential sequence and a first element of the one-dimensional sequence into a binary file; and compressing the binary file using a DEFLATE algorithm. Apparatus is provided for corresponding decompression also.

Abstract: Apparatus is provided for: storing at least one three-dimensional matrix C[M][N][K] of calibration data; performing singular value decomposition of each at least one three-dimensional matrix C[M][N][K] of calibration data to produce at least one first unitary rotation matrix U, at least one diagonal scaling matrix S and at least one second unitary rotation matrix V; and resizing each of the at least one first unitary rotation matrix U, the at least one diagonal scaling matrix S and the at least one second unitary rotation matrix V by removing dimensions therefrom, thereby producing resized matrices U, S and V. Corresponding decompression is also provided.

Abstract: Apparatus comprises a memory configured to store a matrix of transmit data; a multi-element antenna; and a transmitter configured to transmit a signal from a multi-element antenna as part of a packet within a transmit period in a switching interval by: switching between different elements of the multi-element antenna in a sequence of transmit intervals within the transmit period; and deriving the signal for transmission in different transmit intervals from different ones of the transmit data in the matrix. Also, apparatus comprises a receiver configured to receive plural packets; and an accumulator configured, for each packet, to accumulate signals received in a switching interval of the packet. The apparatus is configured to: derive a correlation metric for each of the packets from the accumulated signals for the packets; identify a packet with the best correlation metric; identify a direction associated with the packet identified as having the best correlation metric; and provide the direction as an output.

Abstract: Systems and techniques for decoding of data are described. A plurality of sub-decoders are defined, with the number of sub-decoders being limited only by a number of bits of a codeblock to be processed. A number of iterations is defined for the sub-decoders based on a desired maximum block error rate. Sub-decoders may run asynchronously.