Abstract:
A method of reducing the power consumption of a multi-mode mobile telecommunications device, the method comprising receiving information relating to the location of the mobile telecommunications device and adjusting the frequency with which the mobile telecommunications device searches for a wireless access point according to the information so received.
Abstract:
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.
Abstract:
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.
Abstract:
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 centre of the predetermined frequency band.
Abstract:
A signal receiver having: an input for receiving radio signals; a clock; a receiving section for processing signals received at the input, the receiving section being configured to operate in: (a) a first mode for processing the received signals in accordance with a first protocol and in dependence on the state of the clock, and (b) a second mode for processing the received signal in accordance with a second protocol by steps including storing a sample of data received in accordance with the second protocol together with a representation of the state of the clock when that data was received, and subsequently comparing a timing indicated by the content of the stored sample of data with the timing indicated by the stored state of the clock.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.