A communication unit (200) employs a method and apparatus for increasing an output impedance of a transmit amplifier during a receive mode of the communication unit. The communication unit includes a transmit amplifier, an antenna (209), and a signal receiver (211), and is operable in at least a transmit mode and a receive mode. During the transmit mode, the transmit amplifier, which includes an amplifying device (201), amplifies an input signal (221) and provides the amplified signal (233) to t...

A method for selecting a diversity mode to be applied by a transmitter having two cross-polarized antenna arrays, each representing a diversity branch, comprising the steps of: providing a plurality of diversity mode performance chart look-up tables, mapping a respective individual diversity mode to a respective pair of time correlation value and space correlation value for the two cross-polarized antenna array beams, wherein a respective individual diversity mode is presented by a mapping area,...

The invention concerns a system for transmitting information in a digital radio network system (12) between at least two modes of operation, which may be--a direct mode operation (DMO) between two terminal devices (10.1, 10.2) operating independently of the physical radio network system (21) and--a trunked mode operation (TMO) supporting distribution of network resources and operating in the physical radio network system (21). The transmission takes place with the aid of a special gateway unit (...

Systems and methods for intelligently assigning a channel to a device being used by a mobile user in a power controlled, wireless communications system by minimizing the difference between a mobile user's received signal power and the minimum received signal power of a current user on a candidate carrier frequency. Each carrier frequency within a cell is examined to determine whether it has at least one current user assigned to a channel and also has at least one unoccupied channel. For each car...

A mobile communication terminal having adaptive array antennas is provided that is capable of transmitting signals to an intended base station without interfering other devices, even when a reception error occurs. The mobile communication terminal basically performs array transmission/reception using weight vectors produced in reception to weight and combine signals received via antennas, and thereby receives a desired signal. In transmission, the mobile communication terminal uses the weight ve...

In a communication recording system using a headset with a radio communication function which transmits the first speech signal and receives the second speech signal by radio communications, the headset is provided with a time information acquisition unit for acquiring a time information indicating occurrence times of the first speech signal and the second speech signal, an information production unit for producing a recording information to be stored in which the time information is set in corr...

When an incoming call to a wireless communication apparatus is detected, a wireless control apparatus uses a wireless link, which has been established by previous communication, to perform succeeding communication. Examples of communication include communication of audio or data already completed, or, when there are a plurality of wireless communication apparatus, communication of control information by a wireless link established when notification of an incoming call is given to the wireless co...

A new and significantly improved approach for controlling the transmission power in the uplink direction of a CDMA-based radio system is disclosed, which provides a transmission power control even with regard to an overall link quality substantially involving a real time reaction on changes in the environment. A CDMA-based radio system is described which comprises an inner power control loop for adjusting the transmission power between a user equipment and at least one base station based on the ...

A method for controlling transmission power from a wireless transceiver. Signal to interference ratios (SIRs) are estimated for a signal that is received from another wireless device. An out-of-sync condition between the wireless transceiver and the other wireless device is identified based on the SIRs. Change of the transmission power from the wireless transceiver is restricted based on the SIRs and when an out-of-sync condition has not been identified.

A method and apparatus for transferring information over a communications link includes transmitting information at a first power level, monitoring for correct reception of the transmitted information and transmitting further information at a second, power level other than that used for the original transmission if correct reception did not occur. The further information allows the content of the originally transmitted information to be established and in one embodiment constitutes a retransmiss...