Cambridge Silicon Radio Limited

James Digby Yarlet Collier

Andrei Popescu

Ian Michael Sabberton

Chris Lowe

David Chappaz

Steven Singer

Simon Chang

Noel Andrew Bainbridge

Johan Lucas Gertenbach

Steve Jones

Paul J Wright

Kwangseok Han

Marco Bruno

Stuart Aitken

Justin David John Penfold

An antenna for receiving and/or transmitting radio frequency signals in a predetermined frequency band, the antenna comprising: a first antenna portion comprising at least one conducting loop about a first material having an initial permeability of at least 4; and a second antenna portion embedded within a second material having a dielectric constant of at least 4; wherein the first and second antenna portions are electrically coupled together so as to form a compound antenna having a size such that the diameter of the smallest sphere which encloses all of the first and second antenna portions of the compound antenna is less than 1/30 of the wavelength of the radio frequency signals at the center of the predetermined frequency band.

Internal FM antenna

Receiving a Wi-Fi radio signal using a Bluetooth receiver architecture. Also, adapting a Wi-Fi receiver architecture to constrain a received radio signal to less than the bandwidth of a conveyed Wi-Fi signal for subsequent processing purposes.

Schemes for the efficient reception of radio communications signals

Apparatus for controlling the generation of a DC signal at the output of a mixer, so that the DC signal is predictable, enabling a static offset compensation voltage to offset the DC signal. The apparatus comprises a mixer configured to receive a first and a second input signal, the mixer being such as to generate a first DC signal at the output of the mixer when the first and second input signals have the same frequency and a first relative phase, a phase detector for determining the relative phase of the first and second signals, and a phase modifier configured to modify the phase of the second signal relative to the first signal in dependence on the determination of the relative phase between the first and second signals such that the resulting DC signal at the output of the mixer is the first DC signal.

Architecture to remove a bimodal dynamic DC offset in direct conversion receiver

Improved power control methods and power control systems are described wherein received RSSI values are processed to generate a power control signal which may be used by a link manager, or other element in a receiving station, to determine whether to send a power control message to the transmitting station. The method used to process the received RSSI values is dependent upon a value of the power measurement, for example, the method may involve a comparison between the value of the power measurement and a value of the power control signal. In another embodiment, the received RSSI values may be converted to power values and then smoothed using a filter.

Power control method

A communication device for receiving a signal in the form of a series of bursts, each burst being at one of a plurality of different available transmission modes, the communication device comprising: two antennas; a receiver unit coupled to the antennas for preferentially receiving signals from a selected one of the antennas; and an antenna selection unit for selecting for each received burst with which of the antennas the receiver unit is to preferentially receive signals.

Antenna diversity

Method and peripheral device to facilitate the installation of software on a host device to allow communication between that host device and a peripheral device. On connection to a host device a peripheral device presents in a first mode. In the first mode the device identifies itself as a Human Interaction Device and transmits information to the host device to facilitate the installation of the software. Subsequently the peripheral device operates in a second mode in which it identifies itself according to its real function.

Software install automation

A radio receiver for receiving first signals of a first frequency spectrum having principal energy in a first frequency band and second signals of a second frequency spectrum having principal energy in second and third frequency bands, located on either side of the first frequency band, includes (i) an input for receiving an incoming signal; (ii) frequency shifting means for frequency shifting the incoming signal to form an intermediate frequency signal; and (iii) a filter for filtering the intermediate frequency signal. The filter has a frequency response that has a first passband and a second passband separated by a central stopband. A control unit for controlling the frequency shifting means has first and second modes for reception of the first and second signals. In the first mode, the control unit controls the frequency shifting means so as to frequency shift the incoming signal so that (a) the first frequency band of the incoming signal is shifted onto one of the first and second passbands and (b) one of the second and third frequency bands of the incoming signal is shifted onto the central stopband. In the second mode, the control unit controls the frequency shifting means so as to frequency shift the incoming signal so that (a) the second and third frequency bands of the incoming signal are shifted onto, respectively, the first and second passbands and (b) the first frequency band of the incoming signal is shifted onto the central stopband.

Receiver for multiple signal spectra

A peripheral device having: an interface for connection to a host device; a memory for storing software for use by the host device for operating with the peripheral device; and a processor for controlling the operation of the device such that the device has two operating modes over the interface: a first mode in which it operates as a storage device storing the said software and a second mode in which it operates as a device for providing other functionality to a device connected to it via the interface by means of the software; the peripheral device being configured so that on connection of the interface to a host device it operates in the first mode and so that it subsequently operates in the second mode.

Installing drivers

A method for generating random data, the method comprising repeatedly performing a series of operations, and the series of operations comprising processing a seed value to generate a resulting value for use as the seed value in a subsequent performance of the series of operations and to generate output random data; wherein the series of operations also comprises: determining whether a predetermined amount of new truly random data is available; and if such data is available, modifying the generation of at least the resulting value in dependence on the new truly random data.

Generating random data

A variable frequency oscillator comprising: an oscillatory circuit for generating a periodic output dependent on the capacitance between a first node and a second node of the circuit, and having a capacitative element connected between the first node and the second node; the capacitative element comprising: a variable capacitance unit, the capacitance of which is variable for varying the frequency of the output and a plurality of finite capacitances each being selectively connectable in parallel with the variable capacitance unit between the first node and the second node to trim the frequency of the output.

Variable oscillator

A radio transceiver comprising: an antenna; local oscillator for generating a local oscillator signal at a local oscillator frequency; a receiver capable of receiving a first radio frequency signal from the antenna at a receiver input and having a first mixer for mixing a signal derived from the first radio signal with the said local oscillator signal to generate an intermediate frequency signal, and a receiver output for providing an output signal dependant on the intermediate frequency signal; a transmitter capable of receiving an input signal at a transmitter input and having a second mixer for mixing a signal derived from the input signal with a local oscillator signal to generate a second radio frequency signal for transmission; a switching arrangement having a normal configuration in which the transmitter is coupled to the antenna to apply the second radio frequency signal to the antenna, and a testing configuration in which the transmitter is coupled to the receiver input to apply the second radio frequency signal to the receiver input; and a signal processor coupled to the transmitter input and the receiver output and capable of, when the switching arrangement is in the testing configuration, applying a testing signal to the transmitter input to cause the transmitter to generate a radio frequency test signal, and determining from the output signal of the receiver the response of the receive to the radio frequency test signal.

Testing response of a radio transceiver

A radio transmitter and/or receiver comprising: an oscillator tuning circuit comprising an adjustable capacitor whose capacitance is adjustable by means of a first tuning signal; a filter tuning circuit comprising an adjustable capacitor whose capacitance is adjustable by means of a second tuning signal; an oscillator whose operational frequency is dependant on the reactance of the oscillator tuning circuit; a filter for filtering signals in the course of transmission and/or reception, and whose response is dependant on the reactance of the filter tuning circuit; and a tuning unit for generating the first and second tuning signals; wherein at least a part of the filter tuning circuit is a replica of at least a part of the oscillator tuning circuit and the tuning circuit is capable of generating one of the first and second tuning signals in dependence on the other of the tuning signals.

Adjustable filter

The present invention is directed to a phase shifting arrangement for generating a set of mutually orthogonal signals. In one aspect, the invention provides a system that includes a phase shifting unit for receiving an input signal. The phase shifting unit includes a first phase shift circuit for generating a first output signal phase-shifted by a first amount with respect to the input signal, a second phase shift circuit for generating a second output signal phase-shifted by a second amount with respect to the input signal, and a third phase shift circuit for generating a third output signal phase-shifted by a third amount with respect to the input signal.

Growing community of inventors

Suffolk, United Kingdom

James Digby Yarlet Collier