US 6,487,264 B1 · RF modem apparatus

Abstract

An RF modem used with a host device for transmitting information to, and receiving information from, other host devices. Prior to a transmission, the information is Manchester encoded and transmitted by On/Off Keying. A superregenerative receiver circuit (which may also operate as the transmitter) operating at the transmitted frequency detects the transmitted information. The information is recovered in conjunction with a timing function which times the buildup of RF energy within the receiver circuit so that a transmitted binary 1 can be distinguished from a binary 0. For use in a system with a plurality of hosts, multiple channels of operation are provided. In order to conserve power, the apparatus is operated in a power saving, sleep or scanning mode, as well as a full power active mode.

Claims24

Dependent claims

An RF modem used in conjunction with a host device, comprising:

(A) a superregenerative circuit including an oscillator circuit operable to receive modulated RF information signals;
(B) control means for periodically providing control signals to said superregenerative circuit in a first period to quench oscillations of said oscillator circuit and in a second period to allow buildup of oscillations;
(C) means operable during said second period to obtain a time indication of the time between the beginning of said second period and the time that said oscillations have built up to a predetermined reference level;
(D) means for accumulating said time indications;
(E) means for recovering said information signal based on said accumulated time indications;
and
(F) means for interchanging information with said host device.

4 more elements

An RF modem coupled to a host device, for transmitting RF information signals to, and receiving RE information signals from, another RE modem coupled to a host device, in an array of host devices, comprising:

(A) transmitter/receiver means operable at a plurality of different frequencies, constituting a plurality of separate channels;
(B) control means for providing control signals to said transmitter/receiver means and for establishing an RE signal link with a designated said modem within said array, on a particular one of said channels, whereby other modems of said array can simultaneously establish RF signal links on other channels of said plurality;
(C) said control means being operable to cause said transmitter/receiver means to transmit a plurality of ring packets, each including an initial sync portion, to said designated modem, which, if it successfully receives said ring packet, will acknowledge said receipt by transmitting an acknowledgment signal on said same channel, said acknowledgment signal including an initial sync portion;
(D) said modem, in response to said acknowledgment signal thereafter being operable to transmit to said designated modem, one or more data packets, on said same channel, each said data packet including an initial sync portion;
and
(E) means for interchanging information with said host device.

3 more elements

Dependencies are inferred from the claim text.

RF modem apparatus

Life of this patent

RF modem apparatus

Life of this patent

Abstract

Claims24