Matches 1 - 50 out of 51 1 2 >
Match Document Document Title
6438385 Mobile communication devices  
A method for eliminating the disturbance caused by a mobile station (MS) situated within a certain area 1 . In order to be able to prevent disturbance caused by a mobile station reliably, the...
6363241 Muting systems and methods for communication transceivers  
Muting systems and methods are described that reduce noise signals that are received in a communication hub which communicates with indoor units (IDUs) of a plurality of communication customers....
6115474 Method for removing switching noise during start and end of communication  
A method for removing a noise of a communication system, and more particularly, a method for removing switching noise generated during connecting and disconnecting a channel is provided. A method...
6011806 Cellular telephone communication protocol  
A cellular telephone communication protocol enables a communication link primarily for the transmission of voice and data. At predetermined intervals or on-demand data regarding location, an event,...
5995827 Method of muting a non-speaking cellular telephone caller participating in a conference call  
A facility is provided in wireless communications system which causes a base station to substitute predetermined signals for speech and/or noise signals that are received from a wireless station...
EP0903914A1 Cordless telephone system and method  
A difference circuit measures the time interval between the cutting off of the signal conversation and the frame signal. The connection circuit can be modified to vary the cut off function.
5864762 Operating a trunked communication system in transmission and message trunked modes  
A digitally trunked radio repeater system provides substantial improvements in timeliness and reliability. The mobile radio transceivers transmit channel requests on the control channel at 9600...
5760844 Video signal data and composite synchronization extraction circuit for on-screen display  
A signal voltage level dual clamping circuit is disclosed for use in a receiving circuit for extraction of timing information from a signal. A first, start-up voltage level clamp is provided, the...
5596372 Video signal data and composite synchronization extraction circuit for on-screen display  
A composite synchronization extraction circuit is particularly suited for receiving composite video signals containing closed captioning data in raster scan line 21 by means of a signal CMOS...
5574788 Trunked radio repeater system  
A digitally trunked radio repeater system provides substantial improvements in timeliness of channel acquisition and channel drop, and in reliability of critical control signalling. The system uses...
5564090 Method and apparatus for dynamically adjusting receiver squelch threshold  
An adaptive digital squelch system, responsive to ambient RF background noise, that automatically adjusts the receiver squelch level during intervals when no valid signal is being received. A valid...
5465404 Communications receiver with an adaptive squelch system  
A wireless communications receiver having an adaptive squelch system and operable in multiple states including a receiver (11) that provides a received signal when operating in a clear...
5408693 Muting of radio-transmitter digital audio based on received signal strength  
A radio communication device (10) comprises a radio transceiver (12), having a received signal strength indicator (RSSI) (16), an audio section (22), and a controller (16) for deactivating the...
5408680 Single channel autonomous digitally trunked RF communications system  
A single channel autonomous trunking ("SCAT") RF repeater transmits and receives on a single duplex RF channel. The repeater operates alternately in a control channel mode and in an assigned...
5404172 Video signal data and composite synchronization extraction circuit for on-screen display  
A data and synchronization extraction circuit for processing composite video signals containing closed captioning data is disclosed. A dual mode voltage clamp is realized in CMOS technology which...
5369783 Dynamic regrouping in a trunked radio communications systems  
In a trunked radio frequency communications system, a dynamic regrouping scheme includes an effective user interface, automatic support of multi-site systems, the capability to program individual...
5303407 Digital squelch tail circuit for two-way radio communication systems  
A squelch tail circuit (20) is provided capable of incorporation within integrated circuit structures. A digital timer (26 and 27) provides a time delay based upon a feed-back comparison providing...
5274838 Fail-soft architecture for public trunking system  
A site architecture for a trunked radio frequency communications system provides better fault tolerance capabilities than are available from architectures including redundant hardware. During...
5265093 Hardware interface and protocol for a mobile radio transceiver  
A system and method for communicating control signals between a digital mobile transceiver, a digital control head, and a mobile data terminal over a common serial peripheral bus uses a message...
5212714 High speed data interface for land mobile communication system  
A high speed data interface unit that is fully compatible with existing, trunked, land mobile voice transceivers is provided. Data rates of up to 4800 baud using bilevel modulation are achievable...
5206863 Processor-to-processor communications protocol for a public service trunking system  
A downlink between a communications dispatch console and a digitally trunked radio repeater system site controller efficiently transfers message data between the site controller and the console...
5175866 Fail-soft architecture for public trunking system  
A site architecture for a trunked radio frequency communications system provides better fault tolerance capabilities than are available from architectures including redundant hardware. During...
5151922 Variable speaker muting based on received data  
A method and an apparatus for controlling a speaker mute time is provided to transmit an information message from a first communication device to a second communication device. In response to...
5128930 Processor-to-processor communications protocol for a public service trunking system  
A downlink between a communications dispatch console and a digitally trunked radio repeater system site controller efficiently transfers message data between the site controller and the console...
5125102 Trunked radio repeater system including synchronization of a control channel and working channels  
A digitally trunked radio repeater system provides substantial improvements in timeliness of channel acquisition and channel drop, and in reliability of critical control signalling. The system uses...
5117501 Dynamic regrouping in a trunked radio communications system  
In a trunked radio frequency communications system, a dynamic regrouping scheme includes an effective user interface, automatic support of multi-site systems, the capability to program individual...
5109543 Hardware interface and protocol for a mobile radio transceiver  
A system and method for communicating control signals between a digital mobile transceiver, a digital control head, and a mobile data terminal over a common serial peripheral bus uses a message...
5086506 Radio trunking fault detection system with power output monitoring and on-air monitoring  
A trunked radio frequency (RF) repeater system for public service trunking (PST) or the like includes a fault detection system having an RF output power monitoring, over-the-air RF monitoring and...
5077828 RF channel expansion in a trunked radio communications system  
In a trunked radio frequency communications system, an arrangement dynamically "expands" or extends the frequency allocation table stored within the "personality" defining non-volatile storage...
5063597 Muting circuit in a digital audio system  
A muting circuit in a digital audio system having a digital signal processor, a first latch, a second latch, a comparator for comparing data in the first and second latches, an address encoder, a...
5060296 Communication system with squelch control  
A trunked communication system (100) wherein an EOT (308) as transmitted by a communication unit (103) is used by the system to initiate a squelch methodology, but is not used by the resource...
4939746 Trunked radio repeater system  
A digital trunked radio repeater system provides substantial improvements in timeliness of channel acquisition and channel drop, and in reliability of critical control signalling. The system uses a...
4926496 Method and apparatus for infrequent radio users to simply obtain emergency assistance  
A digital mobile radio transceiver allows even the most unsophisticated user to simply and easily obtain emergency communications. The transceiver is programmed with "personality" data specifying...
4905302 Trunked radio repeater system  
A digitally trunked radio repeater system provides substantial improvements in timeliness of channel acquisition and channel drop, and in reliability of critical control signalling. The system uses...
4905234 Apparatus and method for transmitting digital data over a radio communications channel  
A digital radio RF signalling protocol communicates either digitized voice or digital data signals and indicates the type of information being communicated to the receiver. Multiple repeats of...
4903262 Hardware interface and protocol for a mobile radio transceiver  
A system and method for communicating control signals between a digital mobile transceiver, a digital control head, and a mobile data terminal over a common serial peripheral bus uses a message...
4891824 Muting control circuit  
A muting control circuit is provided in which muting is performed when any one of a plurality of unlock detection signals is detected, indicating circuits is unlocked or when a data error is...
4835731 Processor-to-processor communications protocol for a public service trunking system  
A downlink between a communications dispatch console and a digitally trunked radio repeater system site controller efficiently transfers message data between the site controller and the console...
4821292 Adaptive limiter/detector which changes time constant upon detection of dotting pattern  
A limiter/detector which takes advantage of the characteristics of the dotting pattern preceding each message in the General Electric Public Service Trunking System shortens bit synchronization...
4811370 Digital muting circuit  
A first digital sound data of N-bits delivered from the input terminal is controlled by a mute control signal indicating either on-mute state signifying the state where mute operation is conducted...
4780715 Communication system capable of interruption talk during data transmission  
A communication system may perform talking and data transmission by a polling process which are carried out between a plurality of terminal units and a central control station. The system is...
4716576 Apparatus for controlling transmitter-receiver  
An apparatus for controlling a transmitter-receiver which can transmit and receive an aural signal and a data signal. In the transmission mode, the control apparatus detects a data transmission...
4663765 Data muting method and apparatus for audo-digital communications systems  
An audio muting device for use in a transceiver which receives digital data preceded by a dotting pattern uses a detection/decoder for detecting the non-audible dotting pattern and a controller for...
4661659 Wireless phone system communicatively combined with a computer  
A wireless phone system comprises a master phone unit connectable to a telephoneline, and a wireless phone receiver connectable to the master phone unit, the wireless phone receiver comprising a...
4636791 Data signalling system  
A data signalling system for transmitting signals between at least one primary station and a plurality of secondary stations. The system is well adapted for use in multiple unit radio...
4621365 Synchronization preamble correlation detector and frequency estimator  
A device is disclosed which simultaneously performs sync preamble correlation detection and frequency offset estimation functions for a spread spectrum receiver. The device performs a parallel...
4621361 Communication switching system  
A simple but versatile communication switching system suitable for air traffic control and the like applications is provided. The system utilizes a central pulse amplitude modulation bus, is...
4608455 Processing of encrypted voice signals  
The occurrence of a transmission error which produces a multibit error burst in the decrypted version of a composite speech and synchronization encrypted signal using a one-bit cipher feedback or...
4594591 General purpose data control terminal  
A general purpose data control terminal which permits multiple terminal control. The terminal is programmable thereby permitting compatability with a wide range of communications systems. The unit...
4591851 General purpose data control system  
A general purpose data control and information system particularly well adapted for multiple unit radio communications providing reliable enhancement to normal voice systems. The system provides...
Matches 1 - 50 out of 51 1 2 >