Patent ID: 8472507

Claim:
A radio communication system, comprising a first radio communication device, which comprises: a first communication circuit comprising a non-heterodyne receiver, configured to receive a communication request and to provide a wake-up signal upon receiving the communication request; and a second communication circuit comprising a receiver, a transmitter, or a transceiver, having an operating state and a power saving state, wherein said second communication circuit switches from the power saving state to the operating state upon receiving the wake-up signal from the non-heterodyne receiver, wherein the non-heterodyne receiver is capable of demodulating and decoding the communication request, the communication request being provided in a composite signal; and wherein the non-heterodyne receiver includes multiple detector stages; the composite signal comprising an energy sense (CW) modulation technique, followed by modulation using two or more of the following modulation techniques: a. amplitude-modulation (AM) b. single tone modulation; c. digital data encoding using at least one of: amplitude-shift keying (ASK); On-Off Keying (OOK); frequency-shift keying (FSK); pulse code modulation (PCM); pseudorandom-noise (PN-Code) technique using on-off keying (OOK) or amplitude-shift keying (ASK); d. multiple tones in time sequence; e. multiple tones at the same time; wherein at least one of the two or more modulation techniques includes said digital data encoding.