Topic
Selective calling
About: Selective calling is a research topic. Over the lifetime, 167 publications have been published within this topic receiving 803 citations.
Papers published on a yearly basis
Papers
Patent•
16 Nov 1970TL;DR: In this paper, a selective calling system is proposed, which includes a transmitter having first and second signal generators providing sinusoidal and rectangular signals which are combined to form a modulated calling signal.
Abstract: The selective calling system includes a transmitter having first and second signal generators providing sinusoidal and rectangular signals which are combined to form a modulated calling signal. Each receiver of the system includes a first demodulator which demodulates the modulated calling signal and a second demodulator which demodulates the rectangular signal. A frequency selective device connects the first demodulator to a first input of an AND gate and a repetition rate selective device connects the second demodulator to a second input of the AND gate. If the demodulated frequency and repetition rate are within the passbands of the devices, the AND gate provides a turn-on signal which allows primary information to be reproduced by the receiver. The system can be modified so that auxiliary information is transferred to the receivers by the calling signal.
57 citations
Patent•
12 Jan 1989
TL;DR: In this article, a hybrid remote control system for extending the range of portable RF transceivers and for providing a select-call system is presented, where a modified full duplex system is used to control transmit and receive cycles from the portable unit so that the system can operate regardless of interference on the channel to which the base station is timed.
Abstract: A method and apparatus for extending the range of portable RF transceivers and for providing a select-call system includes a hybrid remote control system to extend the range of a portable transceiver and to permit the operator of a vessel or vehicle to communicate hands-free through the utilization of his own full power base station and antenna, in which a modified full duplex system is used to control transmit and receive cycles from the portable unit so that the system can operate regardless of interference on the channel to which the base station is timed. Also provided is a selective calling system in which a recipient's transceiver is turned on by the transmitting transceiver through punching in the recipient's call letters or at least its address. As an added feature, the transmitting station automatically transmits its own call letters which are displayed at recipient's receiver. This system thereby quiets all receivers until the particular transceiver is digitally addressed. An emergency code such as (0,0,0,0) activates all receivers for emergency transmissions on an emergency channel, such as on VHF channel 16, so that the emergency channel can be monitored without distraction from non-emergency traffic. This modular approach provides a universal system in which standard transceivers can be accommodated.
48 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2013 | 1 |
| 2005 | 3 |
| 2004 | 1 |
| 2003 | 3 |
| 2002 | 2 |
| 2001 | 2 |