Frame format and design of wake-up frame for a wake-up receiver

Patent metadata

Field	Value
Publication number	US-2018019902-A1
Application number	US-201715604220-A
Country	US
Kind code	A1
Filing date	May 24, 2017
Priority date	Jul 14, 2016
Publication date	Jan 18, 2018
Grant date	—

Abstract

Methods and systems for providing a low-rate data signal. Received input data bits are Manchester modulated onto successive multicarrier symbols in the time domain. Each multicarrier symbol includes orthogonal sub-carrier and a null sub-carrier. A stored waveform can be retrieved to code the sub-carriers. The successive multicarrier symbols are up-converted to a carrier frequency to provide the low-rate data signal, and the low-rate data signal is transmitted.

First claim

1 . A method of providing a low-rate data signal, the method comprising:
receiving input data bits; retrieving a stored waveform for coding orthogonal sub-carriers of a multicarrier symbol, the multicarrier symbol including a null sub-carrier; Manchester modulating the input data bits onto successive multicarrier symbols in time domain; up-converting the successive multicarrier symbols to a carrier frequency to provide the low-rate data signal; and transmitting the low-rate data signal over a wireless channel.

2 . The method of claim 1 , wherein generation of the waveform using inverse fast Fourier transform (IFFT) is not required for each transmission.

3 . The method of claim 1 further comprising:
generating the waveform using inverse fast Fourier transform (IFFT); and
storing the waveform.

4 . The method of claim 1 wherein the input data bits are mapped using on-off keying (OOK).

5 . The method of claim 1 wherein the multicarrier symbol comprises M orthogonal sub-carriers, wherein for each successive multicarrier symbol the corresponding data bit is modulated onto each of M−1 of the orthogonal sub-carriers.

6 . The method of claim 5 wherein for each successive multicarrier symbol the corresponding data bit is modulated as “on” and “off” periods of equal duration.

7 . The method of claim 5 wherein M equals 16 and the sub-carriers have an inter-carrier spacing (SS) of 312.5 KHz.

8 . The method of claim 1 further comprising inserting a guard interval period into each of the successive multicarrier symbols.

9 . The method of claim 1 wherein the input data bits are data bits of a wake-up packet and the low-rate data signal is a wake-up signal.

10 . The method of claim 9 wherein the wake-up packet comprises a short training field, the short training field comprising a short training sequence enabling detection of the wake-up packet distinct from other signals.

11 . A method at a receiver, the method comprising:
receiving a low-rate data signal transmitted over a wireless channel; down-converting the low-rate data signal to recover successive multicarrier symbols, each multicarrier symbol comprising a set of orthogonal sub-carriers and a null sub-carrier; and extracting data bits from each of the multicarrier symbols to recover the data bits of the low-rate data.

12 . The method of claim 11 , wherein extracting data bits comprises, for each received multicarrier symbol:
applying an envelope detection operation to the received multicarrier symbol; and applying a decision threshold to the output of envelope detection operation.

13 . The method of claim 11 , wherein extracting data bits comprises, for each received multicarrier symbol:
measuring power distribution of the received multicarrier symbol; and comparing power distribution between first and second halves of the received multicarrier symbol and determining the corresponding data bit to be a “1” or a “0” based on the comparison.

Assignees

• Suh Jung Hoon
• Aboul-Magd Osama
• Au Kwok Shum

Inventors

• Suh Jung Hoon
• Aboul-Magd Osama
• Au Kwok Shum

Classifications

• H04L27/2628

  Inverse Fourier transform modulators, e.g. inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators (H04L27/2634 takes precedence) · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04L27/2607 Primary

  Cyclic extensions · CPC title

• H04L27/26025 Primary

  Numerology, i.e. varying one or more of symbol duration, subcarrier spacing, Fourier transform size, sampling rate or down-clocking (allocating sub-channels of the transmission path H04L5/003) · CPC title

• H04L27/2602

  Signal structure · CPC title