Abstract: A method of acquiring the identity parameters of two or more mobile devices (20), the method comprising: obtaining a list of two or more base stations (1, 2, 3); and acquiring identity parameters from the devices (20) by emulating each base station in the list. Two or more base stations may be simultaneously emulated, and the list of two or more base stations may be obtained by simultaneously interrogating two or more base stations (1, 2, 3). The identity parameters may be IMSI and/or IMEI and/or TMSI codes.

Abstract: A method of determining the direction of a mobile communication device, the method comprising receiving an encoded locator signal from the device over a wireless link; decoding the locator signal to generate a decoded output; and measuring the direction of arrival of the locator signal by analyzing the decoded output. A method of maintaining a connection with a mobile communication device, the method comprising establishing a connection with the device; receiving a request from the device to release the connection; and repeatedly sending a request for information to the device to prevent the device from releasing the connection.

Abstract: The present invention relates to a method and apparatus for forcing a mobile device to handover from a first cellular network radio access technology (RAT) to a second radio access technology (RAT) different from the first cellular network radio access technology. The method comprises: establishing a connection with the mobile device using the first cellular network radio access technology; sending a handover command to the device using the first cellular network radio access technology, the handover command including details of radio resources of the second cellular network radio access technology; and establishing a connection with the mobile device using the radio resources of the second cellular network radio access technology which were specified in the handover command. These steps are each performed by a separately introduced base station which is not under the control of a cellular network.

Abstract: A method of obtaining the directory number (such as the MSISDN) of a mobile device registered with a mobile communication network. The method comprises: causing the mobile device to disconnect from the network and connect with a separately introduced transmitter which is not under the control of the network; sending a request to the mobile device from the separately introduced transmitter, the request including an identification of a convenient device, and causing the mobile device to transmit a response to the network, which in turn causes the network to retrieve the directory number of the mobile device from a database and transmit it to the convenient device; and receiving the directory number from the network at the convenient device.

Abstract: A method of compiling a list of IDs associated with a mobile device user, the method including the steps of: a) identifying and recording a first subscriber ID and a first device ID; b) using one of the first IDs as a key to identify one or more second IDs, each of which has been associated with the key in a mobile device communication; and c) recording the second ID(s).

Abstract: A method of determining the direction of a mobile communication device, the method comprising receiving an encoded locator signal from the device over a wireless link; decoding the locator signal to generate a decoded output; and measuring the direction of arrival of the locator signal by analyzing the decoded output. A method of maintaining a connection with a mobile communication device, the method comprising establishing a connection with the device; receiving a request from the device to release the connection; and repeatedly sending a request for information to the device to prevent the device from releasing the connection.

Abstract: A method of acquiring an identity parameter of a device registered with a network. The device is configured to respond to a set of integrity protected requests from the network only after the device has authenticated the network. The device is also configured to respond to a non-integrity protected identity request from the network without requiring authentication of the network. The method comprises transmitting a false cell broadcast which is not under the control of the network, the false cell broadcast including the non-integrity protected identity request; and receiving the identity parameter from the device in response to the identity request.

Abstract: A method of acquiring the identity parameters of two or more mobile devices (20), the method comprising: obtaining a list of two or more base stations (1, 2, 3); and acquiring identity parameters from the devices (20) by emulating each base station in the list. Two or more base stations may be simultaneously emulated, and the list of two or more base stations may be obtained by simultaneously interrogating two or more base stations (1, 2, 3). The identity parameters may be IMSI and/or IMEI and/or TMSI codes.

Abstract: A method of setting up a call with a mobile communication device, the method comprising transmitting a call request to the device over a wireless link, wherein the call request is adapted to cause the device to transmit a locator signal whilst blocking a connection management process which would otherwise cause the mobile communication device to provide a visual or audible alert. The locator signal can then be used by a direction finder to locate the direction of the device. Channel information is transmitted to the direction finder, the channel information identifying a channel of the locator signal.

Abstract: In a communications between a base station and subscriber unit in time slots within fixed length time frames, different types of messages require different numbers of timeslots per frame to maintain transmission rate. At least a portion of the message is detected to determine the type of message, and if appropriate, additional time slot(s) are assigned.

Abstract: In transmission between a base station and a subscriber unit, system control signals are sent in time slots within fixed length time frames. The system control signals are fragmented, each fragment being sent in a different time slot of a frame.

Abstract: The present invention relates to a method of transmitting digital data messages in predetermined time slots within fixed length time frames from at least one of a plurality of subscriber units to a base station for reception, in which, selectively, subscriber units which are members of one or more predetermined classes of subscriber units are restricted from transmitting at least one predetermined type of message. This advantageously helps in avoiding overload of the network. The invention also relates to corresponding communication means.

Abstract: In a communications network involving transmission of data packets, control messages between nodes are assigned priorities dependent on message type. The allocated of messages to TDM/TDMA time slots is dependent on the assignment priorities.

Abstract: In time domain multiplex/time domain multiple access communications between a base station and subscriber unit, the base station sends a timing reference signal. A subscriber unit responds with a data packet (a) sufficiently short to ensure correct reception by the base irrespective of transmission time. The base determines the transmission time taken and instructs the subscriber unit to advance its timings so that longer data packets (b) can be sent so as to be received when expected. The timing adjustment includes both a fixed present component dependent on approximate separation of base station and subscriber unit, and a second component from measurement of the transmission time taken.