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Monitoring system for radio communication apparatus

  • US 5,027,427 A
  • Filed: 05/30/1989
  • Issued: 06/25/1991
  • Est. Priority Date: 05/28/1988
  • Status: Expired due to Fees
First Claim
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1. A monitoring system for a radio communication apparatus including a base station and a plurality of portable units, said system for monitoring a set of each said portable units through said base station, and comprising:

  • means disposed in said base station for transmitting a first asking signal to each of said portable units at occurrences of a first predetermined period;

    means disposed in each of said portable units for replying a response signal in response to said first asking signal only when an operation state of said portable unit becomes abnormal;

    means disposed in said base station for transmitting a second asking signal to each of said portable units in response to said response signal and at occurrences of a second predetermined period which is longer in time than said first predetermined period; and

    means disposed in each of aid portable units for transmitting a state signal to said base station in response to said second asking signal, said state signal indicating an operation state of said portable unit.

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