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US 11,888,548 B2Granted
Power line communication for low-bandwidth control and sensing
AssigneeMassachusetts Institute of Technology
InventorsSteven B. Leeb, Leslie K. Norford, Erik K. Saathoff, Adedayo O. Aderibole, Kevin Kircher
Life of this patent
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Abstract
Described are power line communication (PLC) systems, devices and techniques which are reliable and suitable for use in control applications which can operate with relatively low data rates while complying with governing regulatory rules. Such systems, devices and techniques enable demand-side management of electrical loads in a building or facility or other environment.
Claims20
A communication system comprising:
- (a) a device;
- (b) a transmission medium;
- and
- (c) a modem coupled between the device and the transmission medium, the modem configured to:
- (c1) receive signals from the device and modulate the received signals for transmission over the transmission medium with a spread spectrum chirp transmitter as modulated spread spectrum chirp signals, transmit the modulated spread spectrum chirp signals as binary data by:
- (a) defining a bit time interval during which a single bit of data is to be communicated;
- (b) converting each data bit to a first signal waveform having a first binary condition in at least one portion of the bit time interval and having the remaining binary condition in other portions of the bit time interval;
- (c) integrating the first signal waveform to obtain a ramp waveform;
- and (d) providing the ramp waveform to a control input of a spread spectrum transmitter;
- (c2) receive modulated spread spectrum chirp signals propagating on the transmission medium, demodulate the received modulated spread spectrum chirp signals and provide demodulated spread spectrum chirp signals to the device;
- and
- (c3) meet quasi-peak (QP) signal levels.
9 more elements
A communication modem for implementing a low bitrate sensing and control protocol over a transmission medium, the communication modem comprising:
- a spread spectrum transmitter configured to transmit spread spectrum signals having a chirp frequency range extending substantially over a quasi-peak (QP) frequency band, the transmitted spread spectrum signals corresponding to low-bitrate, sensing and control signals;
- and
- a spread spectrum receiver configured to receive spread spectrum signals having a chirp frequency range extending substantially over the quasi-peak (QP) frequency band, the received spread spectrum signals corresponding to low-bitrate, sensing and control signals;
- wherein the spread spectrum transmitter is configured to transmit binary data by:
- defining a bit time interval during which a single bit of data is to be communicated;
- converting each data bit to a first signal waveform having a first binary condition in at least one portion of the bit time interval and having the remaining binary condition in other portions of the bit time interval;
- integrating the first signal waveform to obtain a ramp waveform;
- and
- providing the ramp waveform to a control input of the spread spectrum transmitter.
6 more elements
A communication system comprising:
- (a) a device;
- (b) a transmission medium;
- and
- (c) a modem coupled between the device and the transmission medium, the modem configured to:
- (c1) receive signals from the device and modulate the signals for transmission over the transmission medium with a spread spectrum chirp transmitter;
- and
- (c2) receive modulated spread spectrum chirp signals propagating on the transmission medium, (i) frequency-demodulate frequency variations of the received spread spectrum chirp signals;
- (ii) integrate the frequency-demodulated spread spectrum chirp signals;
- (iii) compare the integrated and frequency-demodulated spread spectrum chirp signals with a reference level to recover binary data by obtaining a binary value of each data bit in the received modulated spread spectrum chirp signals;
- and provide the recovered binary data to the device;
- and
- (c3) meet quasi-peak (QP) signal levels.
9 more elements
A communication modem for implementing a low bitrate sensing and control protocol over a transmission medium, the communication modem comprising:
- a spread spectrum transmitter configured to transmit spread spectrum signals having a chirp frequency range extending substantially over a quasi-peak (QP) frequency band, the transmitted spread spectrum signals corresponding to low-bitrate, sensing and control signals;
- and
- a spread spectrum receiver configured to receive spread spectrum signals having a chirp frequency range extending substantially over a quasi-peak (QP) frequency band, the received spread spectrum signals corresponding to low-bitrate, sensing and control signals;
- wherein the spread spectrum receiver is configured to recover binary data contained in an output waveform signal received at the spread spectrum receiver by:
- (i) frequency-demodulating frequency variations of the received signal;
- (ii) integrating the frequency-demodulated signal;
- and
- (iii) comparing the integrated frequency-demodulated signal with a reference level to obtain a binary value of each data bit sent by a spread spectrum transmitter.
5 more elements
Dependencies are inferred from the claim text.