University of Surrey

Mitsubishi Denki Kabushiki Kaisha

Realcell Limited

Cellular Design Services Limited

Simon Saunders

Stephen Michael Leach

Andreas-Albertos Agius

Stephen Leach

Anthony Timson

Daniel Kwan Chong Chew

There is discussed a location system for locating the position of a mobile communications device that communicates with a communication network using wireless signals. The location system includes a receiver which detects a wireless signal transmitted between the mobile communications device and a base station forming part of the communication network, and a processing means which processes the detected wireless signal to extract identification information for the mobile communications device. The extracted identification is stored in a data store in association with data indicative of the base station. The processing means and the data store are independent from the communication network, and therefore do not affect the operation of the mobile network.

System and method for locating a cellular communication device

A diversity switch combiner for use in systems for receiving multi-carrier wideband signals is arranged to determine, during a guard interval, which antenna provides the strongest carrier, for each of a plurality of carrier frequencies. A switch is then operated to select, for the subsequent symbol, that antenna which provides the greatest number of strongest carriers.

Diversity switch combiner

A diversity switch combiner for use in systems for receiving wideband signals is arranged to split the received signal into separate channels each carrying a respective frequency band. Respective switch means are provided for each channel in order to switch the input of each channel between different antennas. A switch control determines the switch setting in accordance with the result of a comparison operation, preferably performed during a guard period, in which the signal qualities for different settings are compared.

A measurement-based prediction method for radiation path loss over a predetermined area comprises the steps of: determining a received signal strength () at least one first station resulting from a transmission of known properties () from at least one second station, the first and second stations having known locations; determining radiation path loss data on the basis of the received signal strengths () and topographical information () of the predetermined area; analyzing the determined radiation path loss data to determine coefficients for a radiation propagation model; applying the radiation propagation model () to generate first predicted radiation path loss data at each of the locations of the first stations and over the predetermined area; determining shadowing values on the basis of differences between the received signal strength () and the first predicted radiation path loss data at each of the locations of the first stations; analysing the shadowing values to yield shadowing parameters representative of the predetermined area; and generating shadowing predictions over the predetermined area on the basis of the shadowing parameters and combining such shadowing predictions with the first predicted radiation path loss data to generate second predicted radiation path loss data over the predetermined area ().

Measurement based prediction method for radiation path loss

A multifilar helix antenna includes helical antenna filaments, each filament having a square waveform pattern along its length, resulting in reduced axial length. A multifilar helix antenna according to the invention includes helical antenna filaments, each filament incorporating a microstrip spur-line band stop filter enabling multi-band operation.

Multifilar helix antennas

A multifilar antenna () comprises n spaced antenna filaments, where n is on integer greater thana matching circuit () for matching the characteristic impedance of the antenna to that of a transmitting and/or receiving apparatus; a weighting circuit () for applying respective gain and phase adjustments to signals passed to or from the n filaments; switch means () associated with each filament for selectively altering the electrical length and/or interconnections of the filaments; means for detecting electrical properties of the multifilar antenna with respect to the frequency, polarisation and/or direction of propagation of a signal to be received or transmitted by the multifilar antenna and/or impedance matching of the antenna; and control means (), responsive to the detective means, for controlling the operation of the matching circuit (), the weighting circuit () and the switch means () to adjust the properties of the multifilar antenna () to suit better a current signal to be received or transmitted.

Adaptive multifilar antenna

A multifilar antenna comprises n spaced antenna filaments, where n is an integer greater than 1; a matching circuit for matching the characteristic impedance of the antenna to that of a transmitting and/or receiving apparatus; a weighting circuit for applying gain and phase adjustments to signals passed to or from the n filaments; switch means associated with at least some of the filaments for selectively altering the electrical length and/or interconnections for the filaments; means for detecting electrical properties of the multifilar antenna with respect to the frequency, polarization and/or direction of propagation of a signal to be received or transmitted by the multifilar antenna and/or impedance matching of the antenna; and control means, responsive to the detecting means, for controlling the operation of the matching circuit, the weighting circuit and the switch means to adjust the properties of the multifilar antenna to suit better a current signal to be received or transmitted.

Growing community of inventors

West Sussex, United Kingdom

Simon Saunders