Backscatter devices and network systems incorporating backscatter devices

A backscatter device comprising:

• an antenna, the antenna configured to backscatter a frequency hopped signal including a first frequency;
• baseband circuitry configured to provide data for transmission;
• a waveform generator configured to provide a square wave having a second frequency and further configured to hop the second frequency in accordance with the frequency hopped signal;
• a sub-carrier phase modulator coupled to the baseband circuitry and the waveform generator, the sub-carrier phase modulator configured to shift the square wave in accordance with the data to provide an output signal;
• and
• a switch coupled to the antenna, the switch configured to control the antenna to backscatter the carrier signal in accordance with the output signal such that the first frequency is mixed with the second frequency to transmit the data in a backscatter signal at a third frequency, wherein the backscatter signal is arranged in accordance with a wireless communication protocol implementing phase-shift keying.

A system comprising:

• a helper device configured to transmit a carrier signal including a first frequency;
• a backscatter device configured to backscatter the carrier signal using sub-carrier shift modulation with a square wave having a second frequency, the backscatter device configured to backscatter the carrier signal into a backscatter signal at a third frequency, the third frequency equal to a combination of the first and second frequencies, wherein the backscatter signal is arranged in accordance with a wireless communication protocol implementing phase-shift keying;
• and
• a receiver configured to receive the backscatter signal at the third frequency.

A backscatter device comprising:

• an antenna configured to backscatter a carrier signal having a first frequency;
• baseband circuitry configured to provide data for transmission;
• a waveform generator configured to provide a waveform having a second frequency, wherein the second frequency is a difference between the first frequency and a third frequency;
• a sub-carrier phase modulator coupled to the baseband circuitry and the waveform generator, the sub-carrier phase modulator configured to adjust a phase, amplitude, or combinations thereof, of the waveform in accordance with the data to provide an output signal;
• and
• a switch coupled to the antenna, the switch configured to control the antenna to backscatter the carrier signal in accordance with the output signal such that the first frequency is mixed with the second frequency to transmit the data in a backscatter signal at the third frequency and a fourth frequency.

A backscatter device comprising:

• an antenna, the antenna configured to backscatter a frequency hopped signal having a sequence of frequencies including a first frequency;
• baseband circuitry configured to provide data for transmission;
• a waveform generator configured to provide a waveform having a second frequency and further configured to hop the second frequency in accordance with the frequency hopped signal;
• a sub-carrier phase modulator coupled to the baseband circuitry and the waveform generator, the sub-carrier phase modulator configured to adjust a phase, amplitude, or combinations thereof, of the waveform in accordance with the data to provide an output signal;
• a switch coupled to the antenna, the switch configured to control the antenna to backscatter the carrier signal in accordance with the output signal such that the first frequency is mixed with the second frequency to transmit the data;
• and
• a memory configured to store the sequence of frequencies.

A backscatter device comprising:

• an antenna, the antenna configured to backscatter a frequency hopped signal including a first frequency;
• baseband circuitry configured to provide data for transmission;
• a waveform generator configured to provide a waveform having a second frequency and further configured to hop the second frequency in accordance with the frequency hopped signal;
• a sub-carrier phase modulator coupled to the baseband circuitry and the waveform generator, the sub-carrier phase modulator configured to adjust a phase, amplitude, or combinations thereof, of the waveform in accordance with the data to provide an output signal;
• a switch coupled to the antenna, the switch configured to control the antenna to backscatter the carrier signal in accordance with the output signal such that the first frequency is mixed with the second frequency to transmit the data;
• and
• a frequency determination circuitry coupled to the antenna, the frequency determination circuitry configured to provide an indication of the second frequency to the waveform generator at least in part by sensing the first frequency of the carrier signal and computing a difference between the first frequency and the third frequency.

A system comprising:

• a helper device configured to transmit a carrier signal including a first frequency;
• a backscatter device configured to backscatter the carrier signal using sub-carrier modulation with a waveform having a second frequency, the backscatter device configured to backscatter the carrier signal into a backscatter signal at a third frequency, the third frequency equal to a combination of the first and second frequencies;
• a receiver configured to receive the backscatter signal at the third frequency;
• and
• a plurality of helper devices including the helper device and a plurality of receivers including the receiver, wherein the helper device is selected from the plurality of helper devices to provide the carrier signal based, at least in part, on a proximity of the helper device to the backscatter device.