System for identifying a responding station for a radio communications system

• US 4,628,537 A
• Filed: 10/18/1983
• Issued: 12/09/1986
• Est. Priority Date: 10/19/1982
• Status: Expired due to Fees

• Current Assignee: Pioneer Electronic Corporation (Pioneer Corporation)
• Original Assignee: Pioneer Electronic Corporation (Pioneer Corporation)
• Inventors: Inoue, Takao, Tsuchiya, Toshiaki, Kawamura, Katsuaki, Shimakata, Masashi, Syoji, Mitsuo, Kuroda, Keiichi, Shioya, Yuichiro
• Primary Examiner(s): NG, JIN FAY
• Application Number:
  US06/543,056
• Time in Patent Office: 1,148 Days
• Field of Search: 455/32, 455/34, 455/31, 455/38, 455/53, 455/54, 455/58, 455/59, 455/77-79, 340/825.5, 340/825.51, 340/825.54, 375/7.9, 371/34, 370/85, 179/2 EB
• US Class Current: 455/516
• CPC Class Codes: H04W 88/022 Selective call receivers

Abstract

A communications system for identifying a responding station called by a communications system caller station over a call channel and a plurality of speech channels. The system transmits information from the caller station, such as the selected speech channel and the designated responding station through the call channel, and receives information from a responding station on the selected speech channel. The communication between the communications system and the responding station on the selected speech channel is enabled only when information from the responding station is identical to information of the designated responding station transmitted from the communications system.

Claims

1. A communications system having a plurality of speech channels one of which is to be selected to convey an information, adapted to perform a simplex communication, comprising:

a searching operation control means for comanding sequential operations of (I) setting the communications system to a receiving state at a speech channel and detecting the presence of a carrier signal and in turn selecting a next speech channel and detecting the presence of a carrier signal if the carrier signal is present at said speech channel, (II) transmitting an audible signal at a selected speech channel at which the carrier signal is not detected, (III) detecting once more the presence of the carrier signal at the selected speech channel, and (IV) memorizing infomation of the selected speech channel as a non-busy speech channel only if the carrier signal is not present at the selected speech channel.

2. A communications system operative as a caller station and having a plurality of speech channels one of which is to be selected to convey an information and adapted to perform simplex communication using a searching operation of a sequence of (I) setting the communications system to a receiving state at a speech channel and detecting the presence of a carrier signal and in turn selecting a next speech channel and detecting the presence of the carrier signal if the carrier signal is present at the speech channel, (II) transmitting an audible signal at a selected speech channel at which the carrier signal is not detected, (III) detecting once more the presence of the carrier signal at the selected speech channel, and (IV) identifying the selected speech channel as a non-busy speech channel only if the carrier signal is not present at the selected speech channel, said communications system having means for receiving an audible signal transmitted from a third station and generating an output signal while a call between the caller station and a responding station is taking place at the selected speech channel, thereby indicating a break on the selected speech channel by means of the output signal of said means for receiving an audible signal.