Abstract: A radio frequency (RF) receiver includes a digital tuning engine; I-path and Q-path analog filters, tuned by the digital tuning engine; and a digital compensation circuit. The digital tuning engine executes a RC (resistor-capacitor) time constant calibration to adjust respective cut-off frequencies of the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter mismatch calibration to match the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter residual mismatch calibration to match an I-path response from the I-path analog filter to the digital compensation circuit and a Q-path response from the Q-path analog filter to the digital compensation circuit.

Abstract: In an up-converter path of a transmitter, wide-band signal system like direct conversion WiGig, a high pass filter (HPF) is placed in the baseband path after the low pass filter (LPF) but before the mixers. The baseband signal of WiGig can have a bandwidth of 800 MHz. The HPF removes the frequencies from 0-40 MHz from the baseband signal and degrades the overall signal of the baseband by a dB or so. However, the frequency pulling is significantly reduced since oscillator frequency and Radio frequency (RF) transmitter frequencies after conversion become further separated when compared a system using to the conventional approach. This causes the injected signal to fall outside the locking range of the oscillator. The concern of substrate coupling is reduced and allows for a reduction in the physical distance between the oscillator and the mixer and reduces a shift in the desired target frequency of operation.

Abstract: A sampling circuit samples a transmission signal containing a particular transmission signal transmitted in a regular and intermittent transmission pattern. The sampling circuit includes a sampling processing unit that performs a sampling process that samples the transmission signal; a determination unit that determines whether the sampling process has been successfully or unsuccessfully performed; and a sampling control unit that sets up sampling acquisition intervals for the sampling processing unit in which the intervals differ depending on whether the sampling process is successfully or unsuccessfully, the sampling processing unit performing the sampling process based on the sampling acquisition interval that has been set up by the sampling control unit.

Abstract: A radio integrated circuit includes, in part, an analog front end block, an analog-to-digital converter responsive to the analog-front end block, a digital signal processor responsive to the analog-to-digital converter and adapted to generate in-phase and quadrature signals, and a serial communication interface configured to receive and transmit the in-phase and quadrature signals. The serial communication interface supplies a gain control signal to the analog front end block when a switch disposed in the radio integrated circuit is in a first position. When the switch is in a second position, a gain control block disposed in the radio integrated circuit receives a gain control signal from the analog-to-digital converter and supplies the gain control signal to the analog front end block. The digital signal processor may be configured to interleave the in-phase and quadrature signals.

Abstract: A method and system for packet synchronization may comprise receiving a plurality of bits from an incoming sample of data. The received plurality of bits may be sliced at a first sampling rate. A logic level of at least one of the received plurality of bits may be determined based on the slicing of the received plurality of bits. The received plurality of bits may be synchronized with a channel access code based on determining the logic level of at least one of the received plurality of bits. The channel access code may be sampled at a higher frequency, to increase the probability of detecting whether the incoming bit is LOGIC 1 or LOGIC 0.

Abstract: A radio base station has at least two radio chains and a precoder for precoding information symbols by a precoding matrix for multi-antenna transmission to a number of user equipment terminals. Precoding matrix statistics representative of phase coherency between at least two radio chains is compiled based on feedback information representative of preferred precoding matrix from one or more user equipment terminals (S1). A relative phase error is then detected between radio chains based on the compiled precoding matrix statistics (S2). It is then possible to compensate or otherwise adjust for the detected relative phase error (S3) based on the compiled precoding matrix statistics.

Abstract: The present invention relates to a refinement of the Alamouti encoding scheme. The Alamouti scheme provides transmitting in a first period, the symbols S1 and S2 and in the next period the symbols—S2* and S1*, wherein S1* is the complex conjugate of S1. The symbols carrying the same information are transmitted on different paths to a receiver. If a disturbance occurs during the first period, the receiver may recover the symbol from symbol S1* in the second time period and vice versa. If no disturbance occurs, the receiver may use both symbols to further improve the transmission quality. An interleaver is provided to increase the transmission distance between redundant symbols, thereby causing the spread delay to be set to a value larger than the maximum length of typical channel disturbance in the communication channel.

Abstract: A duty-cycle modulated bit signalling method and circuit, comprising: signaling bits by virtue of a duty-cycle ratio; wherein the duty-cycle ratio is varied dependent upon the transmission rate of the signalling. A bit period comprises a long phase and a short phase and the duty-cycle therebetween is varied such that the ratio between the duration of the long phase and the duration of the short phase is increased for decreasing transmission rate. The duty-cycle ratio is varied dependent upon the transmission rate of the signalling according to one or more ranges of transmission rate. In a higher transmission rate range the duty-cycle is defined as a fixed ratio, and in a lower transmission range the duty-cycle is defined by a fixed length of the short phase of the bit period.

Abstract: The present invention concerns a method for relaying symbols transferred by a source to a destination in a wireless cellular telecommunication network, the symbols being relayed by a relay, the relay receiving symbols, the symbols being representative of coded bits derived from information bits. The relay: receives symbols, successfully decodes the information bits from the symbols, determines a spectral efficiency to be used for transferring symbols from the number of coded bits transferred by the source prior the successful decoding of information bits, transfers symbols using a modulation that corresponds to the determined spectral efficiency.

Abstract: A method for interference reduction in transmission of at least two single carrier frequency continuous communication beams including producing a first communication signal for a first digital communication link, producing a second communication signal for a second digital communication link, transmitting the first communication signal over a first continuous communication beam at a first frequency, transmitting the second communication signal over a second continuous communication beam at the first frequency, characterized by modifying the first communication signal using transmitter interference cancellation.

Abstract: A portion of a signal under test corresponding to a portion of interest in an eye pattern is easily identified. An eye pattern display area displays an eye pattern that is derived from sample data of a signal under test in a bitmap form and shows frequency information with colors or brightness. A user selects an arbitrary point on the eye pattern display area with a cross-hair shaped mouse cursor, by manipulating a mouse. Thereafter, a waveform passing through the selected point is discriminably displayed, for example, with highlighted display on the eye pattern. Further, the corresponding portion of a waveform in the waveform display area is distinguishably displayed, such as with a highlighted display.

Abstract: In a method of transmitting a data stream from a transmitter in a multiple-input-multiple-output (MIMO) wireless communication system, where the transmitter comprises a plurality of transmit antennas, a discrete Fourier transform (DFT) is applied to the data stream to generate a plurality of symbol sequences; symbols of a first symbol sequence from the plurality of symbol sequences are paired with symbols of a second symbol sequence from the plurality of symbol sequences to generate a plurality of symbol pairs, wherein the pairing results in an orphan symbol; a space-time block code (STBC) is applied to the symbol pairs to generate a plurality of sets of STBC symbols, each set of STBC symbols being associated with a corresponding one of the plurality of antennas; a cyclic delay diversity (CDD) operation is applied to the orphan symbol to generate a plurality of CDD symbols, each CDD symbol being associated with a corresponding one of the plurality of antennas; and each one of the antennas transmits the corres

Abstract: Various embodiments are directed to systems and methods for combining a plurality of codes. The plurality of codes may be binary codes having possible logical values of ?1 and +1 and may comprise an even number of codes. An output of the combining v0,k may be given by: v0=sgn(vi), where vi is the sum of the first plurality of codes at the first time. Embodiments for allocating different power levels among various codes are presented.

Abstract: A system for controllably generating jitter in a serial data stream includes a frequency generator and first and second mixers. The frequency generator is configured to output in-phase and quadrature local oscillator signals with a local oscillator frequency of at least about 5 MHz. The local oscillator frequency varies between a selectable minimum frequency and a selectable maximum frequency. The first mixer is configured to mix a fixed frequency clock signal with the in-phase local oscillator signal to output a first mixer output. The second mixer is configured to mix the fixed frequency clock signal with the quadrature local oscillator signal to output a second mixer output. An adder is configured to add the first and second mixer outputs to produce a frequency-modulated clock signal with a frequency that is about the sum of the fixed frequency and the local oscillator frequency and includes a periodic jitter.

Abstract: The present invention relates to a method in which a base station transmits a downlink signal using 8 antennas may comprise the steps of: mapping a downlink signal to N (1?N?4) layers; precoding the signal mapped to the N layers, by using a specific precoding matrix selected from a pre-stored codebook; subjecting the precoded signal to processing for OFDM symbol generation; and transmitting OFDM symbols through 8 antennas. The pre-stored codebook may comprise precoding matrices for the respective ranks corresponding to N, the pre-stored codebook may consist of 16 codebook indexes, and a portion of the precoding matrices for high ranks in the 16 codebook indexes may be generated from the precoding matrices for low ranks.

Abstract: A radio apparatus comprising: a first transceiver means arranged to receive and transmit packets according to a first protocol; a second transceiver means arranged to receive or transmit packets according to a second, different protocol, the second transceiver means being located such that interference is possible between packets of the first and second protocols; analyzing means for determining a probability that a packet to be transmitted or received by the first transceiver means does not contain only redundant information; and decision means for making a decision based on the determined probability as to whether or not the packet should be respectively transmitted or received. The first transceiver means is arranged to respectively transmit or receive the packet or not according to the decision.

Abstract: A radio base station (BS2) comprises: a transmitter (1412) that transmits, via a plurality of transmission antennas, a radio signal to a first radio terminal having a plurality of reception antennas; a transmission directivity controller (1422) that controls directional beam, which is formed by the transmission antennas, on the basis of feedback information that is fed back from the first radio terminal; and an information acquiring unit (1421) that acquires control information to be used for directing the null points of the directional beam toward a second radio terminal that receives, as an interference signal, the foregoing radio signal during communication with another radio base station. The transmission directivity controller (1422) directs, based on the feedback information and control information, the directional beam toward the first radio terminal and the foregoing null points toward the second radio terminal.

Abstract: A radio communication system comprises a control device that controls a radio station, which uses a plurality of first transmission antennas to transmit a first radio signal, for which a channel A is used, to a radio terminal, and a radio station, which uses a plurality of second transmission antennas to transmit a second radio signal, for which the channel A is used, to a radio terminal. The radio terminal, if having received the second radio signal, transmits, to the radio station, interference information based on the arrival direction from which the second radio signal comes to the radio terminal. Based on the interference information received by the radio base station, the control device transmits, to the radio station, control information to be used for directing, in the arrival direction, the null point of a directional beam formed by the second transmission antennas.

Abstract: A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.

Abstract: A communication device includes: a reception element for receiving a signal treated with a setting of a modulation scheme based on a modulation scheme designation information and a controlling of a transmission power based on the transmission power designation information by an external transmitter, demodulating the received signal based on a modulation scheme control information, and outputting a received data; a reception level measurement element for measuring a signal level of the signal and outputting the reception level; a designation information output element for outputting the transmission power designation information correlated to the modulation scheme designation information and the modulation scheme based on the reception level; and a transmission element for transmitting the modulation scheme designation information and the transmission power designation information for the transmitter.