Abstract:
A radio transmission method and a radio transmitter device for radio transmission of an audio signal from an audio device to a radio receiver is described, wherein an audio signal is received from the audio device; and an RF signal is transmitted simultaneously which is modulated with the audio signal on each of a set of at least two different RF channels. Within each of the transmitted RF signals, information identifying at least the other RF channels in the set of RF channels is included.
Abstract:
The present invention is related to a device arranged for authorising the use of a selected function among at least two functions provided on the device. The device comprises storing means (1) for a function-specific voice pattern linked to the selected function and comparing means (2) arranged for comparing an external input signal with the function-specific voice pattern.
Abstract:
An equalizer for a multi carrier signal for carrying out equalization adapted to each carrier or group of carriers, Fourier transforms the multi carrier signal, and obtains difference terms of the multi carrier signal. Both are input to an adaptive filter, to output equalized signals, wherein decimation is applied to at least some of the difference terms input to the filter. This is notable for enabling the complexity to be reduced for a given performance level. In particular since only non-zero filter taps need to be stored and updated, coefficient memory and coefficient calculation capacity can be reduced. Another way to reduce complexity involves measuring noise for at least some of the carriers, and dynamically adapting the size of the filter on a per carrier basis according to global optimizion euristic algorithms which adapt this filter size based on the comparison between this noise and an optimal performance figure achieved in a previous ISI-ICI free measurement phase.
Abstract:
The present invention is related to a device for generating signals spaced π/X rad apart (X being an integer) comprising
at least one delay cell (15) with a delay approximately corresponding to a phase shift π/X rad, and at least one phase detection system (16) inputting at least two signals (10) delayed by the delay cell(s) (15) and generating a feedback signal (18) to at least one delay cell (15).
Abstract:
The present invention is related to a Phase-Locked Loop with
a main loop comprising a Phase Frequency Detector (1), a Main Charge Pump (2), a Main Loop Filter (3), a Voltage Controlled Oscillator (4) and a Frequency Divider (5), coupled in series, a calibration loop coupled to said Phase Frequency Detector (1) and comprising a Calibration Charge Pump (6) and a Calibration Loop Filter (8'), a Control Logic (9) arranged to control said Frequency Divider (5) and to receive a control input signal, and a Reference Frequency Signal (10) applied to said Phase Frequency Detector (PFD)(1) and to said Control Logic (9) and a calibration signal (11) applied to said calibration loop, wherein the main loop comprises a delay generator (14) controlled by said Control Logic (9) and arranged to receive correction signals from said calibration loop and to send an output signal to said Phase Frequency Detector (1).
Abstract:
A first wireless transceiver apparatus for operating in a part of the RF spectrum which is shared with a co-located second wireless transceiver apparatus, the first wireless transceiver apparatus comprising: a wireless transceiver unit; an arbitration interface for interfacing with an arbitration entity which arbitrates access to the shared part of the RF spectrum between the first wireless transceiver apparatus and the second wireless transceiver apparatus; wherein the arbitration interface is adapted to signal time periods when the wireless transceiver unit is operationaI or requests to be operational; and wherein the arbitration interface is adapted to signal data about the first wireless transceiver apparatus during other time periods.
Abstract:
A baseband processor (20) for a Bluetooth device (80) processes packets according to a protocol stack, and uses a Bluetooth host controller interface (30) to receive packets having given priorities, from a higher protocol level or levels. Packet buffers (B1-Bn) are used to buffer the received packets, and the processor reorders the buffered packets according to their priorities, to output a prioritized stream of packets suitable for transmission by a radio part. By prioritising after the HCI interface, rather than before it, the QOS queues can be effectively located at a lower level in the stack. This means the decision made about the order of transmission of the packets, can take place later, meaning a higher probability that a high priority packet can "pass" queues of lower priority packets, and reach the air interface sooner. The reordering can involve a multiplexer (200) arranged to multiplex packets from multiplee packet buffers according to their priorities.
Abstract:
A multicarrier transmission system uses a set of carriers spaced apart in frequency with a number of bits being assigned to each carrier. A transmitter (3) has a mapper (14) which maps a data signal to a parallel set of constellation values. A frequency domain-to-time domain transform stage (18) converts the set of modulated carriers to a time-domain signal. A peak detector detects when the time-domain signal exceeds a predetermined criterion. A constellation modifier (27) modifies the constellation value of at least one of the carriers to reduce the crest factor of the transmitted signal. A carrier is selected for modifying on the basis of a number of bits allocated to that carrier. The constellation modifier (27) can select an alternative constellation value by an iterative method or by calculation. The constellation modifier (27) can operate entirely in the time-domain.