WO2018163718A1 - Communication apparatus and communication method - Google Patents
Communication apparatus and communication method Download PDFInfo
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- WO2018163718A1 WO2018163718A1 PCT/JP2018/004780 JP2018004780W WO2018163718A1 WO 2018163718 A1 WO2018163718 A1 WO 2018163718A1 JP 2018004780 W JP2018004780 W JP 2018004780W WO 2018163718 A1 WO2018163718 A1 WO 2018163718A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/02—Power saving arrangements
- H04W52/0209—Power saving arrangements in terminal devices
- H04W52/0225—Power saving arrangements in terminal devices using monitoring of external events, e.g. the presence of a signal
- H04W52/0229—Power saving arrangements in terminal devices using monitoring of external events, e.g. the presence of a signal where the received signal is a wanted signal
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03M—CODING; DECODING; CODE CONVERSION IN GENERAL
- H03M5/00—Conversion of the form of the representation of individual digits
- H03M5/02—Conversion to or from representation by pulses
- H03M5/04—Conversion to or from representation by pulses the pulses having two levels
- H03M5/06—Code representation, e.g. transition, for a given bit cell depending only on the information in that bit cell
- H03M5/12—Biphase level code, e.g. split phase code, Manchester code; Biphase space or mark code, e.g. double frequency code
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L27/00—Modulated-carrier systems
- H04L27/02—Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Definitions
- the data field 340 comprises a MAC header 342, a frame body 344 and a FCS (Frame Check Sequence) 346.
- the MAC header 342 and the frame body 344 contain addressing information (e.g., transmitter address and receiver address) and control information.
- the data field 340 is basically OOK modulated.
- inter-sub-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal, without inserting an unnecessary GI in front of the ON sub-symbol.
- the symbol period of the Manchester coded OOK symbols generated according to the first embodiment or the second embodiment of the present disclosure is smaller than the symbol period of the Manchester coded OOK symbols generated according to the third example method as illustrated in Figures 7A and 7B.
- transmission efficiency of the data field 340 modulated by OOK with Manchester code according to the first embodiment or the second embodiment of the present disclosure is improved compared with the third example method as illustrated in Figures 7A and 7B.
- Figures 18A and 18B illustrate example OOK symbol repetitions for information "0" and "1" generated according to a fourth embodiment of the present disclosure.
- An OOK symbol repetition comprises the useful portion of an ON symbol, the useful portion of an OFF symbol and a GI that contains no signal and is placed at the end of the OOK symbol repetition.
- the OOK symbol repetition for information "0” comprises the useful portion of the ON symbol, followed by the useful portion of the OFF symbol and the GI sequentially.
- the OOK symbol repetition for information "1" comprises the useful portion of the OFF symbol, followed by the useful portion of the ON symbol and the GI sequentially.
- the OOK symbol repetitions generated according to the fourth embodiment of the present disclosure is equivalent to the OOK symbol repetitions generated according to the third embodiment of the present disclosure in case of the GI containing no signal. Therefore, according to the fourth embodiment of the present disclosure, by inserting a GI containing no signal at the end portion of the OOK symbol repetition, inter-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal.
- the WUR shifts each detection window by (T SS + T SGI ) to determine whether both the second sub-symbol and the fourth sub-symbol are the OFF sub-symbols for double checking the current symbol repetition detection result, and then shifts each detection window by (3 ⁇ T SS + T SGI ) to decode the next symbol repetition.
- the WUR determines the information corresponding to the current symbol repetition is "1" and shifts each detection window by T sr to decode the next symbol repetition.
- the WUR shifts each detection window by T SS to determine whether both the second sub-symbol and the fourth sub-symbol are the ON sub-symbols for double checking the current symbol repetition detection result, and then shifts each detection window by (3 ⁇ T SS +2 ⁇ T SGI ) to decode the next symbol repetition.
- inter-sub-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal.
- either non-coherent or coherent detector can be used by a WUR to decode the data field 340 of the wake-up packet 300 modulated by OOK with symbol repetition.
- the non-coherent detector e.g., envelop detector
- the MAC Header 342 in the data field 340 of the wake-up packet 300 is modulated by OOK with symbol repetition; while the Frame Body 344 and the FCS 346 in the data field 340 can be modulated by OOK with Manchester code or OOK with symbol repetition.
- OOK with Manchester code can be performed according to the first embodiment or the second embodiment of the present disclosure.
- OOK with symbol repetition can be performed according to the third embodiment, the fourth embodiment, the fifth embodiment, the sixth embodiment, the seventh embodiment or the eighth embodiment of the present disclosure.
- the Manchester coded bipolar OOK symbol for adjacent information "0" comprises the positive ON sub-symbol, followed by the OFF sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "0" comprises the negative ON sub-symbol, followed by the OFF sub-symbol.
- the GI is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol or contains no signal.
- a short GI is inserted in the front of both the ON sub-symbol and the OFF sub-symbol.
- FIGS 34A and 34B illustrate example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to a fourteenth embodiment of the present disclosure.
- the positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’.
- the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is inverted from the polarity of the ON sub-symbol in the preceding Manchester coded bipolar OOK symbol if the spacing between them excluding the GI is equal to or larger than a threshold, high frequency component of the Manchester coded bipolar OOK symbols will be decreased.
- the bipolar OOK symbol repetition for adjacent information "0" or “1” is constructed by concatenating the bipolar OOK symbol for adjacent information "0” and the bipolar OOK symbol for adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment.
- the pattern of concatenating the bipolar OOK symbols for adjacent information "0” and “1” is different between the bipolar OOK symbol repetitions for adjacent information "0" and "1".
- the present disclosure can be realized by software, hardware, or software in cooperation with hardware.
- Each functional block used in the description of each embodiment described above can be partly or entirely realized by an LSI such as an integrated circuit, and each process described in the each embodiment may be controlled partly or entirely by the same LSI or a combination of LSIs.
- the LSI may be individually formed as chips, or one chip may be formed so as to include a part or all of the functional blocks.
- the LSI may include a data input and output coupled thereto.
- the LSI here may be referred to as an IC, a system LSI, a super LSI, or an ultra LSI depending on a difference in the degree of integration.
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Abstract
A communication apparatus of the present disclosure comprises a transmission signal generator which, in operation, generates a transmission signal that includes a legacy preamble, a non-legacy preamble and a data field for a wake-up signal, wherein the data field is modulated by On-Off Keying (OOK) with Manchester code or OOK with symbol repetition; wherein a Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a guard interval (GI) that is placed after the ON sub-symbol; and a transmitter which, in operation, transmits the generated transmission signal.
Description
The present disclosure is generally related to a communication apparatus and a communication method.
The IEEE (Institute of Electrical and Electronics Enigneers) 802.11 Working Group is defining a physical (PHY) layer specification and modifications on medium access control (MAC) layer specification that enable operation of a wake-up radio (WUR) apparatus. The WUR apparatus is a companion radio apparatus to a primary connectivity radio (PCR) apparatus, e.g., IEEE 802.11a/b/g/n/ac/ax radio apparatus. The PCR apparatus included in a wireless communication device is used for user data transmission and reception, which stays in a power save mode unless there is buffered traffic to transmit. The WUR apparatus included in the wireless communication device is not used for user data transmission and reception, which is active only while the PCR apparatus of the device is in a power save mode. Once the WUR apparatus of the device receives a wake-up signal alerting that there is traffic for the PCR apparatus of the device to receive, the device turns on the PCR apparatus.
[NPL 1] IEEE 802.11-16/0341r0, LP-WUR (Low-Power Wake-Up Receiver) Follow-Up, March 2016
[NPL 2] IEEE 802.11-16/1144r0, Further Investigation on WUR Performance, September 2016
[NPL 3] IEEE 802.11-16/1114r0, Coexistence Mechanism for Wakeup Radio Signal, August 2016
[NPL 4] IEEE 802.11-17/0030r0, On the Performance of Timing Synchronization and OOK Pulse Bandwidth, January 2017
[NPL 5] ARIB STD-T55, Dedicated Short Range Communication for Transport Information and Control System, Version 1.0, November 1997
[NPL 6] IEEE 802.11-17/0357r3, A Narrow-Band Bipolar OOK Signal and Modulation Scheme, March 2017
[NPL 7] IEEE 802.11-17/0703r0, Bipolar Pulse Position Modulation, May 2017
[NPL 2] IEEE 802.11-16/1144r0, Further Investigation on WUR Performance, September 2016
[NPL 3] IEEE 802.11-16/1114r0, Coexistence Mechanism for Wakeup Radio Signal, August 2016
[NPL 4] IEEE 802.11-17/0030r0, On the Performance of Timing Synchronization and OOK Pulse Bandwidth, January 2017
[NPL 5] ARIB STD-T55, Dedicated Short Range Communication for Transport Information and Control System, Version 1.0, November 1997
[NPL 6] IEEE 802.11-17/0357r3, A Narrow-Band Bipolar OOK Signal and Modulation Scheme, March 2017
[NPL 7] IEEE 802.11-17/0703r0, Bipolar Pulse Position Modulation, May 2017
Studies are underway to perform efficient transmission of the wake-up signal.
Thus, a non-limiting exemplary embodiment of the present disclosure facilitates providing a communication apparatus that can achieve efficient transmission of the wake-up signal.
In one general aspect, the techniques disclosed here feature a communication apparatus comprising a transmission signal generator which, in operation, generates a transmission signal that includes a legacy preamble, a non-legacy preamble and a data field for a wake-up signal, wherein the data field is modulated by OOK (On-Off Keying) with Manchester code or OOK with symbol repetition; wherein a Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a GI (Guard Interval) that is placed after the ON sub-symbol; and a transmitter which, in operation, transmits the generated transmission signal.
It should be noted that general or specific embodiments may be implemented as a system, a method, an integrated circuit, a computer program, a storage medium, or any selective combination thereof.
By taking advantage of the communication apparatus and the communication method described in the present disclosure, it is possible to achieve efficient transmission of a wake-up signal.
Additional benefits and advantages of the disclosed embodiments will become apparent from the specification and drawings. The benefits and/or advantages may be individually obtained by the various embodiments and features of the specification and drawings, which need not all be provided in order to obtain one or more of such benefits and/or advantages.
The present disclosure can be better understood with the aid of following figures and embodiments. The embodiments described here are merely exemplary in nature and are used to describe some of the possible applications and uses of the present disclosure and should not be taken as limiting the present disclosure with regard to alternative embodiments that are not explicitely described herein.
In any wireless communication system, a wide variety of devices may be a part of the wireless network, each device differing in terms of traffic needs, device capabilities, power supply types and so on. Some class of devices may have high bandwidth requirements, high QoS (Quality of Service) requirements in terms of latency or transmission success rate etc. But they may not be very concerned about power consumption since they may be main-powered or have large batteries (e.g., laptop computers). While another class of devices may have less bandwidth requirements and also less stringent QoS requirements but may be relatively more concerned about power consumption (e.g., mobile phones). Yet another class of devices may have low bandwidth requirements as well as very low duty cycles but may be very sensitive to power consumption due to extremely small batteries or extremely long life expectancy (e.g., sensors for remote sensing).
In many wireless communication systems, there will be one or more central controllers which will determine the wireless network coverage area, the wireless frequency channels, the device admission policy, coordination with other neighboring wireless networks etc. and usually also act as a gateway to the backend infrastructure network. Examples of the central controllers are base stations or eNBs in cellular wireless networks or APs (Access Points) in WLANs (Wireless Local Area Networks).
Even though the techniques described in the present disclosure may apply to many wireless communication systems, for the sake of example, the rest of the descriptions in this disclosure are described in terms of an IEEE 802.11 based WLAN system and its associated terminologies. This should not be taken as limiting the present disclosure with regard to alternative wireless communication systems. In IEEE 802.11 based WLANs, majority of networks operate in infrastructure mode, i.e., all or most of the traffic in the network need to go through the AP. As such, any STA (station) wishing to join the WLAN must first negotiate the network membership with the AP through a process called association and authentication.
Figure 1 illustrates a first example wireless network 100 including an AP 110 and a plurality of STAs. The AP 110 includes a PCR apparatus (hereinafter stated as "PCR") 112. STA 120 represents a device class with high bandwidth and possibly high QoS requirements and relatively low requirement for power saving. The STA 120 is equipped with a PCR 122 but is not equipped with a WUR apparatus (hereinafter stated as "WUR"). STA 130 represents another device class that may also have high bandwidth and possibly high QoS requirements but are relatively more concerned about power consumptions. STA 140 represenst another class of devices that may have low bandwidth requirements but may be very sensitive to power consumption. In order to maximise energy efficiency, the STA 130 is equipped with a WUR 134 in addition to a PCR 132 and the STA 140 is equipped with a WUR 144 in addition to a PCR 142. Both the STA 130 and the STA 140 are termed as WUR STAs thereafter.
For a WUR STA (e.g., STA 130) within the wireless network 100, the PCR 132 of the STA 130, which is used for communicating user data with the AP 110, stays in a power save mode unless there is buffered traffic to send. And the WUR 134 of the STA 130 is active only while the PCR 132 is in a power save mode. Once the WUR 134 receives a wake-up signal transmitted by the AP 110 purposed to alert that there is traffic for the PCR 132 to receive, the STA 130 turns on the PCR 132. The same is true to the other WUR STA 140.
Figure 2 illustrates a second example wireless network 200 including an AP 210 and a plurality of STAs. The AP 210 may be a mobile AP that is more concerned about power consumption. The AP 210 includes a WUR 214 in addition to a PCR 212. STA 220 represents a device class with high bandwidth and possibly high QoS requirements and relatively low requirement for power saving. The STA 220 is equipped with a PCR 222 but is not equipped with a WUR. STA 230 is a WUR STA equiped with a WUR 234 in addition to a PCR 232 and represents another device class that may also have high bandwidth and possibly high QoS requirements but are relatively more concerned about power consumptions. STA 240 is also a WUR STA equipped with a WUR 244 in addition to a PCR 242 and represents another class of devices that may have low bandwidth requirements but may be very sensitive to power consumption.
Within the wireless network 200, both a WUR STA (e.g., STA 230) and the AP 210 may stay in a power save mode. The PCR 212 of the AP 210, which is used for communicating user data with any STA within the wireless network 200, stays in a power save mode unless there is buffered traffic to send. And the WUR 214 of the AP 210 is active only while the PCR 212 is in a power save mode. Once the WUR 214 receives a wake-up signal transmitted by any STA alerting that there is traffic for the PCR 212 to receive, the AP 210 turns on the PCR 212. Similarly, the PCR 232 of the STA 230, which is used for communicating user data with the AP 210, stays in a power save mode unless there is buffered traffic to send; and the WUR 234 of the STA 230 is active only while the PCR 232 is in a power save mode. Once the WUR 234 receives a wake-up signal transmitted by the AP 210 alerting that there is traffic for the PCR 232 to receive, the STA 230 turns on the PCR 232. The same is true to the other WUR STA 240.
Figure 3 illustrates an example format of wake-up packet 300 (see NPL 1). The wake-up packet 300 comprises a legacy preamble 310 and a payload 320. The legacy preamble 310 comprises a L-STF (Legacy Short Training field) 312, a L-LTF (legacy Long Training field) 314 and a L-SIG (legacy Signal field) 316. The legacy preamble 310 is used to facilitate backwards compatibility with the legacy 802.11a/b/g/n/ac/ax standards. The L-STF 312 and L-LTF 314 are primarily used by third party legacy STAs (e.g., STA 120 as illustrated in Figure 1) for packet detection, auto gain control (AGC) setting, frequency offset estimation, time synchronization and channel estimation. The L-SIG 316 is used to assist the third party legacy STAs (e.g., STA 120 as illustrated in Figure 1) in computing the duration of the payload 320 so that they are able to defer their transmissions properly to avoid collison with the wake-up packet 300. The legacy preamble 310 is basically OFDM (Orthogonal Frequency Division Multiplexing) modulated.
The payload 320 comprises a wake-up preamble 330 and a data field 340. The wake-up preamble 330 is used to assist a WUR in detecting the payload 320 and perform symbol synchronization. The wake-up preamble 330 may also be used by the WUR for channel estimation. The wake-up preamble 330 is an OOK (On-Off Keying) modulated symbol based signal. Alternatively, the wake-up preamble 330 is a periodic signal similar to what has been used in 802.11n/ac/ax or a certain training sequence based signal in the time domain similar to what has been used in 802.11ad (see NPL 4).
The data field 340 comprises a MAC header 342, a frame body 344 and a FCS (Frame Check Sequence) 346. The MAC header 342 and the frame body 344 contain addressing information (e.g., transmitter address and receiver address) and control information. The data field 340 is basically OOK modulated.
Figure 4A and 4B illustrate example OOK modulated symbols (hereinafter stated simply as "OOK symbols") for information "0" and "1" generated according to an example method. An OOK symbol for information "0" is represented by ON symbol while an OOK symbol for information "1" is represented by OFF symbol. Basically the OFF symbol contains no signal. Each of the ON symbol and the OFF symbol comprises the useful symbol portion and a GI (Guard Interval), and has a symbol period of Ts = Tu + TLGI where Tu represents the duration of the useful symbol portion and TLGI represents the duration of the GI.
An OFDM modulator can be utilized to generate the ON symbol for information "0" and the OFF symbol for information "1" in the data field 340 of Figure 3 (see NPL 1). For example, suppose that the ON symbol to be generated for information "0" and the OFF symbol to generated for information "1" in the data field 340 have a bandwidth of 4.06 MHz, a symbol period is Ts = 4 microsecond and the subcarrier spacing is 312.5 kHz. The ON symbol can be generated by applying the IDFT (Inverse Discrete Fourier Transform) to 13 consecutive subcarriers that are set to all "1" to generate a 3.2 microsecond signal, followed by 0.8 microsecond cyclic prefix based GI insertion. The OFF symbol can be generated by applying the IDFT to 13 consecutive subcarriers that are set to all "0" to generate a 3.2 microsecond signal, followed by 0.8 microsecond cyclic prefix based GI insertion.
<OOK with Manchester Code>
Notice that in LAA (Licensed Assisted Access), an eNB may initiate a transmission if seven or more consecutive OFF symbols are present in a wake-up signal (see NPL 3). In other words, consecutive OFF symbols in thedata field 340 of the wake-up packet 300 may cause a coexistence problem between IEEE 802.11 based WLAN and LAA. OOK with Manchester code can be applied to the data field 340 in order to combat this problem.
Notice that in LAA (Licensed Assisted Access), an eNB may initiate a transmission if seven or more consecutive OFF symbols are present in a wake-up signal (see NPL 3). In other words, consecutive OFF symbols in the
There are various methods for generating Manchester coded OOK symbols. Figures 5A and 5B illustrate example Manchester coded OOK symbols for information "0" and "1" generated according to a first example method (see NPL 5). A Manchester coded OOK symbol comprises an ON sub-symbol and an OFF sub-symbol, having a symbol period of Ts = 2×Tss where Tss represents the sub-symbol period of the ON sub-symbol or the OFF sub-symbol and Tss = 1/2 ×Tu where Tu represents the duration of the useful symbol portion of the ON symbol or the OFF symbol. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the OFF sub-symbol. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol.
According to the first example method, the Manchester coded symbols generated according to the first example method has a smaller symbol period and thus higher data rate than the uncoded OOK symbols as illustrated in Figures 4A and 4B. However, in multipath environment, without a GI between adjacent sub-symbols, an ON sub-symbol may cause inter-symbol interference to the following symbol or inter-sub-symbol interference to the following sub-symbol within the same symbol.
Figures 6A and 6B illustrate example Manchester coded OOK symbols for information "0" and "1" generated according to a second example method (see NPL 2). A Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a GI that is placed at the beginning of the Manchester coded OOK symbol, having a symbol period of Ts = 2×Tss + TLGI where TLGI represents the duration of the GI. Basically the OFF sub-symbol contains no signal. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the OFF sub-symbol. The GI is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol. The GI is appended in the front of the OFF sub-symbol, which is a cyclic prefix of the OFF sub-symbol.
The ON sub-symbol and the OFF sub-symbol can be generated in a similar manner to the ON symbol and the OFF symbol in Figures 4A and 4B, respectively. For example, in case of Tss = 1.6 microsecond, the ON sub-symbol can be generated by choosing either the first or the second half of the 3.2 microsecond signal that is resulted from applying the IDFT to 13 subcarriers with subcarrier indices of -6 to 6 where every even indexed subcarrier (i.e., subcarriers indexed by -6, -4, -2, 0, 2, 4 and 6) is set to 1 and every odd indexed subcarrier (i.e., subcarriers indexed by -5, -3, -1, 1, 3 and 5) is set to 0. The OFF sub-symbol can be generated by choosing either the first or the second half of the 3.2 microsecond signal that is resulted from applying the IDFT to 13 subcarriers that are set to all 0.
According to the second example, the Manchester coded OOK symbols generated according to the second example method has the same symbol period and data rate as the uncoded OOK symbols as illustrated in Figures 4A and 4B. In addition, by inserting a GI between adjacent symbols, inter-symbol interference can be avoided. However, without a GI between sub-symbols within the same symbol, an ON sub-symbol may cause inter-sub-symbol interference to the following sub-symbol within the same symbol.
Figures 7A and 7B illustrate example Manchester coded OOK symbols for information "0" and "1" generated according to a third example method (see NPL 2). A Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and two short GIs that are placed in the front of the ON sub-symbol and the OFF sub-symbol, respectively, having a symbol period of Ts = 2×Tss + 2×TSGI where TSGI represents the duration of each short GI and TSGI = 1/2 ×TLGI. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the OFF sub-symbol. One of the two short GIs is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol. The other short GI is appended in the front of the OFF sub-symbol, which is a cyclic prefix of the OFF sub-symbol. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol. One of the short GIs is appended in the front of the OFF sub-symbol, which is a cyclic prefix of the OFF sub-symbol. The other short GI is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol.
According to the third example, the Manchester coded symbols generated according to the third example method has the same symbol period and data rate as the uncoded OOK symbols as illustrated in Figures 4A and 4B. In addition, by inserting a GI between neighbouring sub-symbols, inter-sub-symbol interference and inter-symbol interference may be avoided. However, regarding the Manchester coded OOK symbol for information "1", the GI in front of the ON sub-symbol may be redundant since the OFF sub-symbol contains no signal and may not cause inter-sub-symbol interference to the following ON sub-symbol.
Study is underway to improve transmission efficiency of the data field that is modulated by OOK with Manchester code. Next, according to the present disclosure, various embodiments of modulating the data field (e.g., the data field 340 in Figure 3) of the wake-up packet by OOK with Manchester code will be explained in further details.
<First Embodiment>
Figures 8A and 8B illustrate example Manchester coded OOK symbols for information "0" and "1" generated according to a first embodiment of the present disclosure. A Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a GI that follows the ON sub-symbol, having a symbol period of Ts = 2×Tss + TGI where Tss represents the duration of a sub-symbol and TGI represents the duration of the GI. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the GI and the OFF sub-symbol sequentially. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol and the GI sequentially.
Figures 8A and 8B illustrate example Manchester coded OOK symbols for information "0" and "1" generated according to a first embodiment of the present disclosure. A Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a GI that follows the ON sub-symbol, having a symbol period of Ts = 2×Tss + TGI where Tss represents the duration of a sub-symbol and TGI represents the duration of the GI. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the GI and the OFF sub-symbol sequentially. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol and the GI sequentially.
According to the first embodiment of the present disclosure, the GI can be a cyclic postfix of the preceding ON sub-symbol or the GI can contain no signal. Generating Manchester coded OOK symbols with no signal based GI is simpler and consumes less power than generating Manchester coded OOK symbols with cyclic postfix based GI. Figures 9A and 9B illustrate example Manchester coded OOK symbols generated according to the first embodiment of the present disclosure in case of the GI containing no signal. Figures 10A and 10B illustrate example Manchester coded OOK symbols generated according to the first embodiment of the present disclosure in case of the GI based on cyclic postfix.
Generally, non-coherent detector (e.g., envelop detector) or coherent detector (e.g., DFT (Discrete Fourier Transform)-based frequency domain equalizer) can be used to decode Manchester coded OOK symbols. An envelop detector consumes less power than a DFT-based frequency domain equalizer but the latter has a better error performance. In addition, the DFT-based frequency domain equalizer can be used to decode the Manchester coded OOK symbols with cyclic postfix based GI but cannot be used to decode the Manchester coded OOK symbols with no signal based GI. As a result, the GI containing no signal is preferable if the DFT-based frequency domain equalizer is not used by a WUR. Otherwise the GI based on cyclic postfix may be used for better error performance if the DFT-based frequency domain equalizer can be used by a WUR.
According to the first embodiment of the present disclosure, by inserting a GI right after the ON sub-symbol, inter-sub-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal, without inserting an unnecessary GI in front of the ON sub-symbol.
<Second Embodiment>
Figure 11A and 11B illustrates example Manchester coded OOK symbols for information "0" and "1" generated according to a second embodiment of the present disclosure. A Manchester coded OOK symbol of the second embodiment comprises an ON sub-symbol, an OFF sub-symbol and a GI that contains no signal and is placed at the end of each Manchester coded OOK symbol. The symbol period of the Manchester coded OOK symbols is Ts = 2×Tss + TGI. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the OFF sub-symbol and the GI sequentially. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol and the GI sequentially.
Figure 11A and 11B illustrates example Manchester coded OOK symbols for information "0" and "1" generated according to a second embodiment of the present disclosure. A Manchester coded OOK symbol of the second embodiment comprises an ON sub-symbol, an OFF sub-symbol and a GI that contains no signal and is placed at the end of each Manchester coded OOK symbol. The symbol period of the Manchester coded OOK symbols is Ts = 2×Tss + TGI. In more details, the Manchester coded OOK symbol for information "0" comprises the ON sub-symbol, followed by the OFF sub-symbol and the GI sequentially. On the other hand, the Manchester coded OOK symbol for information "1" comprises the OFF sub-symbol, followed by the ON sub-symbol and the GI sequentially.
It should be noted that the Manchester coded OOK symbols generated according to the second embodiment of the present disclosure is equivalent to the Manchester coded OOK symbols generated according to the first embodiment of the present disclosure in case of the GI containing no signal. Therefore, according to the second embodiment of the present disclosure, by inserting a GI that contains no signal and is placed at the end of each Manchester coded OOK symbol, inter-sub-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal, without inserting an unnecessary GI in front of the ON sub-symbol.
In case of TGI = TSGI, the symbol period of the Manchester coded OOK symbols generated according to the first embodiment or the second embodiment of the present disclosure is smaller than the symbol period of the Manchester coded OOK symbols generated according to the third example method as illustrated in Figures 7A and 7B. As a result, transmission efficiency of the data field 340 modulated by OOK with Manchester code according to the first embodiment or the second embodiment of the present disclosure is improved compared with the third example method as illustrated in Figures 7A and 7B.
In case of TGI = TLGI, the symbol period of the Manchester coded OOK symbols generated according to the first embodiment or the second embodiment of the present disclosure is the same as the symbol period of the Manchester coded OOK symbols generated according to the third example method as illustrated in Figures 7A and 7B. As a result, transmission efficiency of the data field 340 modulated by OOK with Manchester code according to the first embodiment or the second embodiment of the present disclosure is the same as the third example method as illustrated in Figures 7A and 7B, but has better delay tolerance than the latter since a shorter GI is used in the latter.
Figures 12A and 12B illustrate example Manchester coded OOK symbols for information "0" and "1" generated according to the first embodiment of the present disclosure in case of the GI containing no signal or the second embodiment of the present disclosure. Figure 13 illustrates example Manchester coded OOK symbols for information sequence "001"generated according to the first embodiment of the present disclosure in case of the GI containing no signal or the second embodiment of the present disclosure.
According to the first embodiment or the second embodiment of the present disclosure, either non-coherent or coherent detector can be used by a WUR to decode the data field 340 of the wake-up packet 300 modulated by OOK with Manchester code. Generally, the non-coherent detector (e.g., envelop detector) consumes less power than the coherent detector but has poorer error performance.
According to the first embodiment or the second embodiment of the present disclosure, prior to decoding the data field 340 of the wake-up packet 300 modulated by OOK with Manchester code (see Figure 3), the WUR shall perform payload detection and time synchronization by using the wake-up preamble 330 of the wake-up packet 300. The WUR may also perform channel estimation by using the wake-up preamble 330 of the wake-up packet 300 if the coherent detector is used by the WUR. To prevent the inter-symbol interference caused by the wake-up preamble 330 to the data 340, a GI can be placed in front of the first OOK symbol of the data field 340. Alternatively, the wake-up preamble 330 can be designed in such a manner that it ends with an OFF symbol. Notice that an OFF symbol may not cause inter-symbol interference to the following symbol.
According to the first embodiment or the second embodiment of the present disclosure, an example decoding procedure performed by a WUR is described below:
For a current symbol, if the first sub-symbol is determined to be the ON sub-symbol within a detection window with a duration of TSS, the WUR determines the information corresponding to the current symbol is "0", and then shifts the detection window by Ts to decode the next symbol. Alternatively, the WUR shifts the detection window by (TSS + TGI) to determine whether the second sub-symbol is the OFF sub-symbol for double checking the current symbol detection result, and then shifts the detection window by TSS to decode the next symbol. On the other hand, if the first sub-symbol of the current symbol is determined to be the OFF sub-symbol within the detection window, the WUR determines the information corresponding to the current symbol is "1", and then shifts the detection window by Ts to decode the next symbol. Alternatively, the WUR shifts the detection window by TSS to determine whether the second sub-symbol is the ON sub-symbol for double checking the current symbol detection result, and then shifts the detection window by (TSS + TGI) to decode the next symbol.
<OOK with Symbol Repetition>
Next, OOK with symbol repetition is described herewith.
Next, OOK with symbol repetition is described herewith.
For non-coherent detection, OOK with symbol repetition in the time domain may be required for a better error performance. Figures 14A and 14B illustrate example OOK symbol repetitions for information "0" and "1" generated according to an example method. An OOK symbol repetition comprises an ON symbol and an OFF symbol, having a symbol repetition period of Tsr = 2×(Tu+TLGI). In more details, the OOK symbol repetition for information "0" comprises the ON symbol, followed by the OFF symbol. On the other hand, the OOK symbol repetition for information "1" comprises the OFF symbol, followed by the ON symbol.
According to the example method for generating OOK symbol repetitions as illustrated in Figures 14A and 14B, regarding the OOK symbol repetition for information "1", the GI at the beginning of the ON symbol may be redundant since the OFF symbol contains no signal and may not cause inter-symbol interference to the following ON symbol.
Study is underway to improve transmission efficiency of the data field 340 of the wake-up packet of Figure 3 modulated by OOK with symbol repetition. Next, according to the present disclosure, various embodiments of modulating the data field 340 by OOK with symbol repetition will be explained in further details.
<Third Embodiment>
Figures 15A and 15B illustrate example OOK symbol repetitions generated according to a third embodiment of the present disclosure. An OOK symbol repetition comprises the useful portion of an ON symbol, the useful portion of an OFF symbol and a GI that follows the useful portion of the ON symbol, having a symbol repetition period of Tsr =2×Tu+TLGI. In more details, the OOK symbol repetition for information "0" comprises the useful portion of the ON symbol, followed by the GI and the useful portion of the OFF symbol sequentially. On the other hand, the OOK symbol repetition for information "1" comprises the useful portion of the OFF symbol, followed by the useful portion of the ON symbol and the GI sequentially.
Figures 15A and 15B illustrate example OOK symbol repetitions generated according to a third embodiment of the present disclosure. An OOK symbol repetition comprises the useful portion of an ON symbol, the useful portion of an OFF symbol and a GI that follows the useful portion of the ON symbol, having a symbol repetition period of Tsr =2×Tu+TLGI. In more details, the OOK symbol repetition for information "0" comprises the useful portion of the ON symbol, followed by the GI and the useful portion of the OFF symbol sequentially. On the other hand, the OOK symbol repetition for information "1" comprises the useful portion of the OFF symbol, followed by the useful portion of the ON symbol and the GI sequentially.
According to the third embodiment of the present disclosure, the GI is a cyclic postfix of the useful portion of the preceding ON symbol or the GI contains no signal. Generating OOK symbol repetitions with no signal based GI is simpler and consumes less power than generating OOK symbol repetitions with cyclic postfix based GI. Figures 16A and 16B illustrate example OOK symbol repetitions generated according to the third embodiment of the present disclosure in case of the GI containing no signal. Figures 17A and 17B illustrate example OOK symbol repetitions generated according to the third embodiment of the present disclosure in case of the GI based on cyclic postfix. Generally, non-coherent detector (e.g., envelop detector) or coherent detector (e.g., DFT-based frequency domain equalizer) can be used to decode OOK symbol repetitions. An envelop detector consumes less power than a DFT-based frequency domain equalizer but the latter has a better error performance. In addition, the DFT-based frequency domain equalizer can be used to decode the OOK symbol repetitions with cyclic postfix based GI but cannot be used to decode the OOK symbol repetitions with no signal based GI. As a result, the GI containing no signal is preferable if the DFT-based frequency domain equalizer is not used by a WUR. The GI based on cyclic postfix may be used for better error performance is the DFT-based frequency domain equalizer can be used by a WUR.
According to the third embodiment of the present disclosure, by inserting a GI after the useful portion of the ON symbol, inter- symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal.
<Fourth Embodiment>
Figures 18A and 18B illustrate example OOK symbol repetitions for information "0" and "1" generated according to a fourth embodiment of the present disclosure. An OOK symbol repetition comprises the useful portion of an ON symbol, the useful portion of an OFF symbol and a GI that contains no signal and is placed at the end of the OOK symbol repetition. The symbol repetition period of the OOK symbol repetition is Tsr = 2×Tu + TLGI. In more details, the OOK symbol repetition for information "0" comprises the useful portion of the ON symbol, followed by the useful portion of the OFF symbol and the GI sequentially. On the other hand, the OOK symbol repetition for information "1" comprises the useful portion of the OFF symbol, followed by the useful portion of the ON symbol and the GI sequentially.
Figures 18A and 18B illustrate example OOK symbol repetitions for information "0" and "1" generated according to a fourth embodiment of the present disclosure. An OOK symbol repetition comprises the useful portion of an ON symbol, the useful portion of an OFF symbol and a GI that contains no signal and is placed at the end of the OOK symbol repetition. The symbol repetition period of the OOK symbol repetition is Tsr = 2×Tu + TLGI. In more details, the OOK symbol repetition for information "0" comprises the useful portion of the ON symbol, followed by the useful portion of the OFF symbol and the GI sequentially. On the other hand, the OOK symbol repetition for information "1" comprises the useful portion of the OFF symbol, followed by the useful portion of the ON symbol and the GI sequentially.
It should be noted that the OOK symbol repetitions generated according to the fourth embodiment of the present disclosure is equivalent to the OOK symbol repetitions generated according to the third embodiment of the present disclosure in case of the GI containing no signal. Therefore, according to the fourth embodiment of the present disclosure, by inserting a GI containing no signal at the end portion of the OOK symbol repetition, inter-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal.
The symbol repetition period of the OOK symbol repetitions generated according to the third embodiment or the fourth embodiment of the present disclosure is smaller than the symbol repetition period of the OOK symbol repetitions generated according to the example method as illustrated in Figures 14A and 14B. As a result, transmission efficiency of the data field 340 modulated by OOK with symbol repetition according to the third embodiment or the fourth embodiment of the present disclosure is improved compared with the example method as illustrated in Figures 14A and 14B.
Figures 19A and 19B illustrate example OOK symbol repetitions for information "0" and "1" according to the third embodiment of the present disclosure in case of the GI containing no signal or the fourth embodiment of the present disclosure. Figure 20 illustrates example OOK symbol repetitions for information sequence "001" according to the third embodiment of the present disclosure in case of the GI containing no signal or the fourth embodiment of the present disclosure.
According to the third embodiment or the fourth embodiment of the present disclosure, either non-coherent or coherent detector can be used by a WUR to decode the data field 340 of the wake-up packet 300 modulated by OOK with symbol repetition. Generally, the non-coherent detector (e.g., envelop detector) consumes less power than the coherent detector and but achieve poorer error performance.
According to the third embodiment or the fourth embodiment of the present disclosure, prior to decoding the data field 340 of the wake-up packet 300 modulated by OOK with symbol repetition, the WUR shall perform payload detection and time synchronization by using the wake-up preamble 330 of the wake-up packet 300. The WUR may also perform channel estimation by using the wake-up preamble 330 of the wake-up packet 300 if the coherent detector is used by the WUR. To prevent the inter-symbol interference caused by the wake-up preamble 330 to the data field 340, a GI can be placed in front of the first OOK symbol of the data field 340. Alternatively, the wake-up preamble 330 can be designed in such a manner that it ends with an OFF symbol. Notice that an OFF symbol may not cause inter-symbol interference to the following symbol.
According to the third embodiment or the fourth embodiment of the present disclosure, an example decoding procedure performed by a WUR is described below:
For a current symbol repetition, if the useful portion of the first symbol is determined to be that of the ON symbol within a detection window with a duration of Tu, the WUR determines the information corresponding to the current symbol repetition is "0", and then shifts the detection window by Tsr to decode the next symbol repetition. Alternatively, the WUR shifts the detection window by (Tu + TLGI) to determine whether the useful portion of the second symbol corresponds to the OFF symbol for double checking the current symbol repetition detection result, and then shifts the detection window by Tu to decode the next symbol repetition. On the other hand, if the useful portion of the first symbol of the current symbol repetition is determined to be that of the OFF symbol within the detection window, the WUR determines the information corresponding to the current symbol repetition is "1", and then shifts the detection window by Tsr to decode the next symbol repetition. Alternatively, the WUR shifts the detection window by Tu to determine whether the useful portion of the second symbol corresponds to the ON symbol for double checking the current symbol repetition detection result, and then shifts the detection window by (Tu + TLGI) to decode the next symbol repetition.
<Fifth Embodiment>
Figures 21A and 21B illustrate example OOK symbol repetitions generated according to a fifth embodiment of the present disclosure. The OOK symbol repetition for information "0" or "1" is generated by simply repeating the corresponding Manchester coded OOK symbol generated according to the first embodiment of the present disclosure twice, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI.
Figures 21A and 21B illustrate example OOK symbol repetitions generated according to a fifth embodiment of the present disclosure. The OOK symbol repetition for information "0" or "1" is generated by simply repeating the corresponding Manchester coded OOK symbol generated according to the first embodiment of the present disclosure twice, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI.
According to the fifth embodiment of the present disclosure, by inserting a GI after the ON sub-symbol, inter-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal.
<Sixth Embodiment>
Figures 22A and 22B illustrate example OOK symbol repetitions generated according to a sixth embodiment of the present disclosure. The OOK symbol repetition for information "0" or "1" is generated by simply repeating the corresponding Manchester coded OOK symbol generated according to the second embodiment of the present disclosure twice, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI.
Figures 22A and 22B illustrate example OOK symbol repetitions generated according to a sixth embodiment of the present disclosure. The OOK symbol repetition for information "0" or "1" is generated by simply repeating the corresponding Manchester coded OOK symbol generated according to the second embodiment of the present disclosure twice, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI.
According to the fifth embodiment or the sixth embodiment of the present disclosure, an OOK symbol repetition comprises a first Manchester coded OOK symbol and a second Manchester coded OOK symbol that correspond to the same information. For example, the OOK symbol repetition for information "0" comprises the first Manchester coded OOK symbol for information "0" and the second Manchester coded OOK symbol for information "0".
Notice that Tss= 1/2 ×Tu and TSGI= 1/2 ×TLGI. The symbol repetition period of the OOK symbol repetitions generated according to the fifth embodiment or the sixth embodiment of the present disclosure is smaller than the symbol repetition period of the OOK symbol repetitions generated according to the example method as illustrated in Figures 14A and 14B. As a result, transmission efficiency of the data field 340 modulated by OOK with symbol repetition according to the fifth embodiment or the sixth embodiment of the present disclosure is improved compared with the example method as illustrated in Figures 14A and 14B.
According to the fifth embodiment or the sixth embodiment of the present disclosure, either non-coherent or coherent detector can be used by a WUR to decode the data field 340 of the wake-up packet 300 modulated by OOK with symbol repetition. Generally, the non-coherent detector (e.g., envelop detector) consumes less power than the coherent detector and but achieve poorer error performance.
According to the fifth embodiment or the sixth embodiment of the present disclosure, prior to decoding the data field 340 of the wake-up packet 300 modulated by OOK with symbol repetition, the WUR shall perform payload detection and time synchronization by using the wake-up preamble 330 of the wake-up packet 300. The WUR may also perform channel estimation by using the wake-up preamble 330 of the wake-up packet 300 if the coherent detector is used by the WUR. To prevent the inter-symbol interference caused by the wake-up preamble 330 to the data field 340, a GI can be placed in front of the first OOK symbol of the data field 340. Alternatively, the wake-up preamble 330 can be designed in such a manner that it ends with an OFF symbol. Notice that an OFF symbol may not cause inter-symbol interference to the following symbol.
According to the fifth embodiment or the sixth embodiment of the present disclosure, an example decoding procedure performed by a WUR is described below:
For a current symbol repetition, if both the first sub-symbol within a first detection window with a duration of TSS and the third sub-symbol within a second detection window with a duration of TSS are determined to be the ON sub-symbols, the WUR determines the information corresponding to the current symbol repetition is "0" and shifts each detection window by Tsr to decode the next symbol repetition. Alternatively, the WUR shifts each detection window by (TSS + TSGI) to determine whether both the second sub-symbol and the fourth sub-symbol are the OFF sub-symbols for double checking the current symbol repetition detection result, and then shifts each detection window by (3×TSS + TSGI) to decode the next symbol repetition. On the other hand, if both the first sub-symbol within the first detection window and the third sub-symbol within the second detection window are determined to be the OFF sub-symbols, the WUR determines the information corresponding to the current symbol repetition is "1" and shifts each detection window by Tsr to decode the next symbol repetition. Alternatively, the WUR shifts each detection window by TSS to determine whether both the second sub-symbol and the fourth sub-symbol are the ON sub-symbols for double checking the current symbol repetition detection result, and then shifts each detection window by (3×TSS +2×TSGI) to decode the next symbol repetition.
<Seventh Embodiment>
Figures 23A and 23B illustrate example OOK symbol repetitions generated according to a seventh embodiment of the present disclosure. An OOK symbol repetition for information "0" or "1" is constructed by concatenating the Manchester coded OOK symbol for information "0" and the Manchester coded OOK symbol for information "1" generated according to the first embodiment of the present disclosure, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI. The pattern of concatenating the Manchester coded OOK symbols for information "0" and "1" is different between the OOK symbol repetitions for information "0" and "1". For example, for the OOK symbol repetition for information "0", the Manchester coded OOK symbol for information "0" is placed in front of the Manchester coded OOK symbol for information "1"; while for the OOK symbol repetition for information "1", the Manchester coded OOK symbol for information "1" is placed in front of the Manchester coded OOK symbol for information "0".
Figures 23A and 23B illustrate example OOK symbol repetitions generated according to a seventh embodiment of the present disclosure. An OOK symbol repetition for information "0" or "1" is constructed by concatenating the Manchester coded OOK symbol for information "0" and the Manchester coded OOK symbol for information "1" generated according to the first embodiment of the present disclosure, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI. The pattern of concatenating the Manchester coded OOK symbols for information "0" and "1" is different between the OOK symbol repetitions for information "0" and "1". For example, for the OOK symbol repetition for information "0", the Manchester coded OOK symbol for information "0" is placed in front of the Manchester coded OOK symbol for information "1"; while for the OOK symbol repetition for information "1", the Manchester coded OOK symbol for information "1" is placed in front of the Manchester coded OOK symbol for information "0".
According to the seventh embodiment of the present disclosure, by inserting a GI after the ON sub-symbol, inter-sub-symbol interference can be decreased, thus increasing the transmission efficientcy of the wake-up signal.
<Eighth Embodiment>
Figures 24A and 24B illustrate example OOK symbol repetitions generated according to an eighth embodiment of the present disclosure. An OOK symbol repetition for information "0" or "1" is constructed by concatenating the Manchester coded OOK symbol for information "0" and the Manchester coded OOK symbol for information "1" generated according to the second embodiment of the present disclosure, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI. The pattern of concatenating the Manchester coded OOK symbols for information "0" and "1" is different between the OOK symbol repetitions for information "0" and "1". For example, for the OOK symbol repetition for information "0", the Manchester coded OOK symbol for information "0" is placed in front of the Manchester coded OOK symbol for information "1"; while for the OOK symbol repetition for information "1", the Manchester coded OOK symbol for information "1" is placed in front of the Manchester coded OOK symbol for information "0".
Figures 24A and 24B illustrate example OOK symbol repetitions generated according to an eighth embodiment of the present disclosure. An OOK symbol repetition for information "0" or "1" is constructed by concatenating the Manchester coded OOK symbol for information "0" and the Manchester coded OOK symbol for information "1" generated according to the second embodiment of the present disclosure, having a symbol repetition period of Tsr = 4×Tss + 2×TSGI. The pattern of concatenating the Manchester coded OOK symbols for information "0" and "1" is different between the OOK symbol repetitions for information "0" and "1". For example, for the OOK symbol repetition for information "0", the Manchester coded OOK symbol for information "0" is placed in front of the Manchester coded OOK symbol for information "1"; while for the OOK symbol repetition for information "1", the Manchester coded OOK symbol for information "1" is placed in front of the Manchester coded OOK symbol for information "0".
According to the seventh embodiment or the eighth embodiment of the present disclosure, an OOK symbol repetition comprises a first Manchester coded OOK symbol and a second Manchester coded OOK symbol that correspond to different information. For example, the OOK symbol repetition for information "0" comprises the first Manchester coded OOK symbol for information "0" and the second Manchester coded OOK symbol for information "1".
Notice that Tss= 1/2 ×Tu and TSGI= 1/2 ×TLGI. The symbol repetition period of the OOK symbol repetitions generated according to the seventh embodiment or the eighth embodiment of the present disclosure is smaller than the symbol repetition period of the OOK symbol repetitions generated according to the example method as illustrated in Figures 14A and 14B. As a result, transmission efficiency of the data field 340 modulated by OOK with symbol repetition according to the seventh embodiment or the eighth embodiment of the present disclosure is improved compared with the example method as illustrated in Figures 14A and 14B.
According to the seventh embodiment or the eighth embodiment of the present disclosure, either non-coherent or coherent detector can be used by a WUR to decode the data field 340 of the wake-up packet 300 modulated by OOK with symbol repetition. Generally, the non-coherent detector (e.g., envelop detector) consumes less power than the coherent detector and but achieve poorer error performance.
According to the seventh embodiment or the eighth embodiment of the present disclosure, prior to decoding the data field 340 of the wake-up packet 300 that is modulated by OOK with symbol repetition, the WUR shall perform payload detection and time synchronization by using the wake-up preamble 330 of the wake-up packet 300. The WUR may also perform channel estimation by using the wake-up preamble 330 of the wake-up packet 300 if the coherent detector is used by the WUR. To prevent the inter-symbol interference caused by the wake-up preamble 330 to the data field 340, a GI can be placed in front of the first OOK symbol of the data field 340. Alternatively, the wake-up preamble 330 can be designed in such a manner that it ends with an OFF symbol. Notice that an OFF symbol may not cause inter-symbol interference to the following symbol.
According to the seventh embodiment or the eighth embodiment of the present disclosure, an example decoding procedure performed by a WUR is described below:
For a current symbol repetition, if the first sub-symbol within a first detection window with a duration of TSS is determined to be the ON sub-symbol and the third sub-symbol within a second detection window with a duration of TSS is determined to be the OFF sub-symbol, the WUR determines the information corresponding to the current symbol repetition is "0" and shifts each detection window by Tsr to decode the next symbol repetition. Alternatively, the WUR shifts the first detection windown by (TSS + TSGI) to determine whether the second sub-symbol is the OFF sub-symbol and shifts the second detection windown by TSS to determine the fourth sub-symbol is the ON sub-symbol for double checking the current symbol repetition detection result, and then shifts the first detection window by (3×TSS + TSGI) and shifts the second detection window by (3×TSS + 2×TSGI) to decode the next symbol repetition. On the other hand, if the first sub-symbol within the first detection window is determined to be the OFF sub-symbol and the third sub-symbol within the second detection window is determined to be the ON sub-symbol, the WUR determines the information corresponding to the current symbol repetition is "1" and shifts each detection window by Tsr to decode the next symbol repetition. Alternatively, the WUR shifts the first detection windown by TSS to determine whether the second sub-symbol is the ON sub-symbol and shifts the second detection windown by (TSS + TSGI) to determine the fourth sub-symbol is the OFF sub-symbol for double checking the current symbol repetition detection result, and then shifts the first detection window by (3×TSS + 2×TSGI) and shifts the second detection window by (3×TSS +TSGI) to decode the next symbol repetition.
<Nineth Embodiment>
According to a nineth embodiment of the present disclosure, thedata field 340 of the wake-up packet 300 including the MAC Header 342, the Frame Body 344 and the FCS 346 can be modulated by OOK with Manchester code or OOK with symbol repetition. OOK with Manchester code can be performed according to the first embodiment or the second embodiment of the present disclosure. OOK with symbol repetition can be performed according to the third embodiment, the fourth embodiment, the fifth embodiment, the sixth embodiment, the seventh embodiment or the eighth embodiment of the present disclosure.
According to a nineth embodiment of the present disclosure, the
According to the nineth embodiment of the present disclosure, a WUR STA (e.g., STA 130 in the wireless network 100 or STA 230 in the wireless network 200) needs to declare its OOK decoding capability during capability exchange. For example, the WUR STA needs to declare whether it supports non-coherent detection only or support both coherent detection and non-coherent detection. Whether OOK with Manchester code or OOK with symbol repetition is used to modulate the data field 340 depends on recipient WUR STA’s OOK decoding capability only. For example, if the recipient WUR STA supports non-coherent detection only, OOK with symbol repetition is used for better error performance. If the recipient WUR STA supports coherent detection, OOK with Manchester code is used for better transmission efficiency. Consequently, the tradeoff between transmission efficiency and error performance is achieved according to recipient WUR STA’s OOK decoding capability only.
According to the nineth embodiment of the present disclosure, no signaling for indicating whether OOK with Manchester code or OOK with symbol repetition is used to modulate the data field 340 is required in the wake-up packet 300.
<Tenth Embodiment>
According to a tenth embodiment of the present disclosure, theMAC Header 342 in the data field 340 of the wake-up packet 300 is modulated by OOK with symbol repetition; while the Frame Body 344 and the FCS 346 in the data field 340 can be modulated by OOK with Manchester code or OOK with symbol repetition. OOK with Manchester code can be performed according to the first embodiment or the second embodiment of the present disclosure. OOK with symbol repetition can be performed according to the third embodiment, the fourth embodiment, the fifth embodiment, the sixth embodiment, the seventh embodiment or the eighth embodiment of the present disclosure.
According to a tenth embodiment of the present disclosure, the
According to the tenth embodiment of the present disclosure, a WUR STA (e.g., STA 130 in the wireless network 100 or STA 230 in the wireless network 200) needs to declare its OOK decoding capability during capability exchange. For example, the WUR STA needs to declare whether it supports non-coherent detection only or support both coherent detection and non-coherent detection. Whether OOK with Manchester code or OOK with symbol repetition is used to modulate the Frame Body 344 and the FCS 346 depends on recipient WUR STA’s OOK decoding capability and channel condition. For example, if the recipient WUR STA supports non-coherent detection only and channel quality is good, OOK with Mancester code is used for better transmission efficiency. If the recipient WUR STA supports non-coherent detection only and channel quality is poor, OOK with symbol repetition is used for better error performance. If the recipient WUR STA supports coherent detection and no matter what the channel quality is, OOK with Manchester code is used for better transmission efficiency. Consequently, the better tradeoff between transmission efficiency and error performance can be achieved according to recipient WUR STA’s OOK decoding capability and channel condition.
According to the tenth embodiment of the present disclosure, a signaling for indicating whether OOK with Manchester code or OOK with symbol repetition is used to modulate the Frame Body 344 and the FCS 346 in the data field 340 is required in the wake-up packet 300. For example, such a signaling is carried in the MAC Header 342.
According to any previous embodiment of the present disclosure, various spread spectrum based methods may be used to generate the ON sub-symbol or the useful portion of the ON symbol for the purpose of achieving better resistence to multipath fading. Example spread spectrum based methods include
- CSS (Chirp Spread Spectrum) which has been used in the IEEE 802.15.4a;
- DSSS (Direct Sequence Spread Spectrum) with Barker code which has been used in the IEEE 802.11b;
- DFT-spread OFDM with Zadoff-Chu sequence which has been used in the LTE (Long-Term Evolution) uplink; and
- Multicarrier OOK.
- CSS (Chirp Spread Spectrum) which has been used in the IEEE 802.15.4a;
- DSSS (Direct Sequence Spread Spectrum) with Barker code which has been used in the IEEE 802.11b;
- DFT-spread OFDM with Zadoff-Chu sequence which has been used in the LTE (Long-Term Evolution) uplink; and
- Multicarrier OOK.
<Configuration of a WUR apparatus>
Figure 25 is a simple block diagram of anexample WUR 2500 which is capable of receiving wake-up signal. The WUR 2500 may be the WUR 134 in the STA 130 or the WUR 144 in the STA 140 as illustrated in Figure 1. The WUR 2500 may also be the WUR 214 in the AP 210, the WUR 234 in the STA 230 or the WUR 244 in the STA 240 as illustrated in Figure 2. The WUR 2500 comprises a receiver 2510 and wake-up signal processing circuitry 2520. The receiver 2510 is responsible for reception of a wake-up signal, and the wake-up signal processing circuitry 2520 is responsible for processing the received wake-up signal.
Figure 25 is a simple block diagram of an
Figure 26 is a detailed block diagram of the example WUR 2500 which is capable of receiving a wake-up signal. The receiver 2510 of the WUR 2500 comprises a RF (Radio Frequency) and Analog Front-end circuitry 2610. The wake-up signal processing circuitry 2520 of the WUR 2500 comprises Payload Detection & Synchronization circuitry 2622, OOK Detection circuitry 2624, Coding Control circuitry 2626 and MAC Processing circuitry 2630. The RF and Analoy Front-end circuitry 2610 is responsible for converting received RF wake-up signal to digital baseband wake-up signal. The Payload Detection & Synchronization circuitry 2622 is responsible for detecting the payload of a wake-up packet contained in the digital baseband wake-up signal and performing symbol synchronization by using the wake-up preamble of the wake-up packet. It may perform channel estimation as well. The OOK Detection circuitry 2624 is responsible for decoding the data field of the wake-up packet modulated by OOK with Manchester code or OOK with symbol repetition under the control of the Coding Control circuitry 2626 according to the various embodiments of the present disclosure. The MAC Processing circuitry 2630 is responsible for processing the decoded data field (e.g., checking the FCS and parsing the MAC Header, etc.).
The WUR 2500 may comprise many other components that are not illustrated, for sake of clarity, in Figure 25 and Figure 26. Only those components that are most pertinent to the present disclosure are illustrated.
<Configuration of a PCR apparatus>
Figure 27 is a simple block diagram of anexample PCR 2700 which is capable for transmitting wake-up signal. The PCR 2700 may be the PCR 112 in the AP 110 as illustrated in Figure 1. The PCR 2700 may also be the PCR 212 in the AP 210, the PCR 232 in the STA 230 or the PCR 242 in the STA 240 as illustrated in Figure 2. The PCR 2700 comprises a wake-up signal generator 2710 and a transmitter 2720. The wake-up signal generator 2710 is responsible for generating a wake-up signal and the transmitter 2720 is responsible for transmission of the generated wake-up signal.
Figure 27 is a simple block diagram of an
Figure 28 is a detailed block diagram of the example PCR 2700 which is capable for transmitting a wake-up signal. The wake-up signal generator 2710 of the PCR 2700 comprises MAC Processing circuitry 2810, Legacy Preamble Generation circuitry 2822, Wake-up Preamble Generation circuitry 2824, OOK Waveform Generation circuitry 2826 and Coding Control circuitry 2828. The MAC Processing circuitry 2810 is responsible for generating the information required for the data field of a wake-up packet. The Legacy Preamble Generation circuitry 2822 is used to generate the legacy preamble of a wake-up packet, the Wake-up Preamble Generation circuitry 2824 is used to generate the wake-up preamble of a wake-up packet. The OOK Waveform Generation circuitry 2826 is responsible for generating the data field of a wake-up packet modulated by OOK with Manchester code or OOK with symbol repetition under the control of the Coding Control circuitry 2828 according to the various embodiments of the present disclosure. The transmitter 2720 of the PCR 2700 comprises a RF and Analog Front-end circuitry 2830 that is responsible for converting digital baseband wake-up signal containing the generated wake-up packet to RF wake-up signal.
The PCR 2700 may comprise many other components that are not illustrated, for sake of clarity, in Figure 27 and Figure 28. Only those components that are most pertinent to the present disclosure are illustrated. In particular, the PCR 2700 comprises a standard Wi-Fi signal transceiver that is responsible for transmission and reception of a standard Wi-Fi signal (e.g., 802.11a/b/g/n/ac/ax signal). Notice that the Legacy Preamble Generation circuitry 2822, the RF and Analog Front-end circuitry 2830, and part of the OOK Waveform Generation circuitry 2826 (e.g., IDFT circuitry) can be shared with the standard Wi-Fi signal transceiver.
<Configuration of a WUR apparatus>
Figure 29 is a simple block diagram of anexample WUR 2900 which is capable of both transmitting and receiving wake-up signal. The WUR 2900 may be the WUR 214 in the AP 210, the WUR 234 in the STA 230 or the WUR 244 in the STA 240 as illustrated in Figure 2. The WUR 2900 comprises a wake-up signal generator 2910, wake-up signal processing circuitry 2930 and transceiver 2920. The wake-up signal generator 2910 is responsible for generating a wake-up signal. The transceiver 2920 is responsible for both transmission of the generated wake-up signal and reception of wake-up signal. The wake-up signal processing circuitry 2930 is responsible for processing the received wake-up signal.
Figure 29 is a simple block diagram of an
Figure 30 is a detailed block diagram of the example WUR 2900 which is capable of both transmitting and receiving wake-up signal. The transceiver 2920 of the WUR 2900 comprises a RF and Analog Front-end circuitry 3040. The wake-up signal generator 2910 of the WUR 2900 comprises Legacy Preamble Generation circuitry 3022, Wake-up Preamble Generation circuitry 3024 and OOK Waveform Generation circuitry 3026. The wake-up signal processing circuitry 2930 of the WUR 2900 comprises a Payload Detection & Synchronization circuitry 3030 and an OOK Detection circuitry 3032. In addition, both the wake-up signal generator 2910 and the wake-up signal processing circuitry 2930 share a MAC Processing circuitry 3010 and a Coding Control circuitry 3028. The RF and Analoy Front-end circuitry 3040 is responsible for converting received RF wake-up signal to digital baseband wake-up signal or converting digital baseband wake-up signal containing generated wake-up packet to RF wake-up signal. The Legacy Preamble Generation circuitry 3022 is used to generate the legacy preamble of a wake-up packet, the Wake-up Preamble Generation circuitry 3024 is used to generate the wake-up preamble of a wake-up packet. The OOK Waveform Generation circuitry 3026 is responsible for generating the data field of a wake-up packet modulated by OOK with Manchester code or OOK with symbol repetition under the control of the Coding Control circuitry 3028 according to the various embodiments of the present disclosure. The Payload Detection & Synchronization circuitry 3030 is responsible for detecting the payload of a wake-up packet contained in the digital basedband wake-up signal and performing symbol synchronization by using the wake-up preamble of the wake-up packet. It may perform channel estimation as well. The OOK Detection circuitry 3032 is responsible for decoding the data field from the digital baseband wake-up signal modulated by OOK with with Manchester code or symbol repetition according to the various embodiments of the present disclosure. The MAC Processing circuitry 3010 is responsible for processing the decoded data field (e.g., checking the FCS, parsing the MAC Header, etc.) or generating the information required for the data field of a wake-up packet.
The WUR 2900 may comprise many other components that are not illustrated, for sake of clarity, in Figure 29 and Figure 30. Only those components that are most pertinent to the present disclosure are illustrated.
<Bipolar OOK with Manchester Code>
Study is underway on how to efficiently modulate the data field by bipolar OOK with Manchester code. The inventors of the present disclosure have performed various study on how to modulate the data field efficiently by using bipolar OOK with Manchester code. Then the inventors of the present disclosure came up with a new idea of "adjacent information" and "non- adjacent information," details of which will be described below. Next, various embodiments of modulating the data field (e.g., thedata field 340 in Figure 3) of the wake-up packet by bipolar OOK with Manchester code will be explained in further details.
Study is underway on how to efficiently modulate the data field by bipolar OOK with Manchester code. The inventors of the present disclosure have performed various study on how to modulate the data field efficiently by using bipolar OOK with Manchester code. Then the inventors of the present disclosure came up with a new idea of "adjacent information" and "non- adjacent information," details of which will be described below. Next, various embodiments of modulating the data field (e.g., the
The <Configuration of a WUR apparatus> and <Configuration of a PCR apparatus> explained above based on Figures 25-30 are also applicable to the following embodiments.
<Eleventh Embodiment>
Figures 31A and 31B illustrate example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to an eleventh embodiment of the present disclosure. A Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol and an OFF sub-symbol, having a symbol period of Ts = 2×Tss. The positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’. The adjacent information "0" means that an information bit in an information sequence is "0" and at least one of its two adjacent information bits is also "0". The adjacent information "1" means that an information bit in an information sequence is "1" and at least one of its two adjacent information bits is also "1". The non-adjacent information "0" means that an information bit in an information sequence is "0" and neither of its two adjacent information bits is "0". The non-adjacent information "1" means that an information bit in an information sequence is "1" and neither of its two adjacent information bits is "1".
Figures 31A and 31B illustrate example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to an eleventh embodiment of the present disclosure. A Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol and an OFF sub-symbol, having a symbol period of Ts = 2×Tss. The positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’. The adjacent information "0" means that an information bit in an information sequence is "0" and at least one of its two adjacent information bits is also "0". The adjacent information "1" means that an information bit in an information sequence is "1" and at least one of its two adjacent information bits is also "1". The non-adjacent information "0" means that an information bit in an information sequence is "0" and neither of its two adjacent information bits is "0". The non-adjacent information "1" means that an information bit in an information sequence is "1" and neither of its two adjacent information bits is "1".
According to the eleventh embodiment, the Manchester coded bipolar OOK symbol for adjacent information "0" comprises the positive ON sub-symbol, followed by the OFF sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "0" comprises the negative ON sub-symbol, followed by the OFF sub-symbol. On the other hand, the Manchester coded bipolar OOK symbol for adjacent information "1" comprises the OFF sub-symbol, followed by the positive ON sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "1" comprises the OFF sub-symbol, followed by the negative ON sub-symbol.
The Manchester coded bipolar OOK symbols generated according to the eleventh embodiment can prevent consecutive OFF symbols and thus avoid the coexistence problem with LAA.
<Twelfth Embodiment>
According to this embodiment, a GI is inserted at the head portion of each Manchester coded bipolar OOK symbol.
According to this embodiment, a GI is inserted at the head portion of each Manchester coded bipolar OOK symbol.
Figures 32A and 32B illustrate example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to a twelfth embodiment of the present disclosure. A Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that is placed at the beginning of the Manchester coded bipolar OOK symbol, having a symbol period of Ts = 2×Tss + TLGI. The positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’. In more details, the Manchester coded bipolar OOK symbol for adjacent information "0" comprises the positive ON sub-symbol, followed by the OFF sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "0" comprises the negative ON sub-symbol, followed by the OFF sub-symbol. The GI is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol or contains no signal. On the other hand, the Manchester coded bipolar OOK symbol for adjacent information "1" comprises the OFF sub-symbol, followed by the positive ON sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "1" comprises the OFF sub-symbol, followed by the negative ON sub-symbol. The GI is appended in the front of the OFF sub-symbol, which contains no signal.
According to the twelfth embodiment, by inserting a GI at the head portion of each Manchester coded bipolar OOK symbol, inter-symbol interference due to a positive or negative ON sub-symbol can be avoided.
<Thirteenth Embodiment>
According to this embodiment, a short GI is inserted in the front of both the ON sub-symbol and the OFF sub-symbol.
According to this embodiment, a short GI is inserted in the front of both the ON sub-symbol and the OFF sub-symbol.
Figures 33A and 33B illustrate example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to a thirteenth embodiment of the present disclosure. A Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and two short GIs that are placed in the front of the ON sub-symbol and the OFF sub-symbol, respectively, having a symbol period of Ts = 2×Tss + 2×TSGI. The positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’.
As illustrated in Figure 33A, the Manchester coded bipolar OOK symbol for adjacent information "0" comprises the positive ON sub-symbol, followed by the OFF sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "0" comprises the negative ON sub-symbol, followed by the OFF sub-symbol. One of the two short GIs is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol or contains no signal. The other short GI is appended in the front of the OFF sub-symbol, which contains no signal.
On the other hand, as illustrated in Figure 33B, the Manchester coded bipolar OOK symbol for adjacent information "1" comprises the OFF sub-symbol, followed by the positive ON sub-symbol; and the Manchester coded bipolar OOK symbol for non-adjacent information "1" comprises the OFF sub-symbol, followed by the negative ON sub-symbol. One of the short GIs is appended in the front of the OFF sub-symbol, which contains no signal. The other short GI is appended in the front of the ON sub-symbol, which is a cyclic prefix of the ON sub-symbol or contains no signal.
According to the thirteenth embodiment, by inserting a short GI in the front of both the ON sub-symbol and the OFF sub-symbol, inter-sub-symbol interference and inter-symbol interference may be avoided. More specifically, inter-sub-symbol interference that may be caused by the ON sub-symbol to the following sub-symbol within the same symbol may be avoided.
<Fourteenth Embodiment>
According to this embodiment, a GI is inserted only after the ON sub-symbol and will not be inserted after the OFF sub-symbol.
According to this embodiment, a GI is inserted only after the ON sub-symbol and will not be inserted after the OFF sub-symbol.
Figures 34A and 34B illustrate example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to a fourteenth embodiment of the present disclosure. In this embodiment, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that follows the ON sub-symbol, having a symbol period of Ts = 2×Tss + TGI. The positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’.
As illustrated in Figure 34A, the Manchester coded bipolar OOK symbol for adjacent information "0" comprises the positive ON sub-symbol, followed by the GI and the OFF sub-symbol sequentially; and the Manchester coded bipolar OOK symbol for non-adjacent information "0" comprises the negative ON sub-symbol, followed by the GI and the OFF sub-symbol sequentially. The GI is a cyclic postfix of the preceding ON sub-symbol or contains no signal.
On the other hand, as illustrated in Figure 34B, the Manchester coded bipolar OOK symbol for adjacent information "1" comprises the OFF sub-symbol, followed by the positive ON sub-symbol and the GI sequentially; and the Manchester coded bipolar OOK symbol for non-adjacent information "1" comprises the OFF sub-symbol, followed by the negative ON sub-symbol and the GI sequentially. The GI is a cyclic postfix of the preceding ON sub-symbol or contains no signal.
According to the fourteenth embodiment, by inserting a GI only after the ON sub-symbol, inter-sub-symbol interference and inter-symbol interference may be avoided while avoiding redundant insertion of a GI in front of the positive or negative ON sub-symbol.
<Fifteenth Embodiment>
According to this embodiment, a GI that contains no signal is placed at the end of each Manchester coded bipolar OOK symbol.
According to this embodiment, a GI that contains no signal is placed at the end of each Manchester coded bipolar OOK symbol.
Figure 35A and 35B illustrates example Manchester coded bipolar OOK symbols for information "0" and "1" generated according to a fifteenth embodiment of the present disclosure. A Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that contains no signal and is placed at the end of each Manchester coded bipolar OOK symbol. The symbol period of the Manchester coded bipolar OOK symbols is Ts = 2×Tss + TGI. The positive ON sub-symbol is used in the Manchester coded bipolar OOK symbol for adjacent information "0" or "1; while the negative ON sub-symbol is used in the Manchester coded bipolar OOK symbol for non-adjacent information "0" or "1’.
As illustrated in Figure 35A, the Manchester coded OOK symbol for adjacent information "0" comprises the positive ON sub-symbol, followed by the OFF sub-symbol and the GI sequentially; and the Manchester coded bipolar OOK symbol for non-adjacent information "0" comprises the negative ON sub-symbol, followed by the OFF sub-symbol and the GI sequentially. On the other hand, as illustrated in Figure 35B, the Manchester coded bipolar OOK symbol for adjacent information "1" comprises the OFF sub-symbol, followed by the positive ON sub-symbol and the GI sequentially; and the Manchester coded bipolar OOK symbol for non-adjacent information "1" comprises the OFF sub-symbol, followed by the negative ON sub-symbol and the GI sequentially.
It should be noted that the Manchester coded bipolar OOK symbols generated according to the fifteenth embodiment of the present disclosure is equivalent to the Manchester coded bipolar OOK symbols generated according to the fourteen embodiment of the present disclosure in case of the GI containing no signal. Therefore, according to the fifteenth embodiment, by inserting a GI containing no signal at the end portion of the Manchester coded bipolar OOK symbol, inter-sub-symbol interference and inter-symbol interference may be avoided while avoiding redundant insertion of a GI in front of the positive or negative ON sub-symbol.
In case of TGI = TSGI, the symbol period of the Manchester coded bipolar OOK symbols generated according to the fourteen embodiment or the fifteenth embodiment of the present disclosure is smaller than the symbol period of the Manchester coded bipolar OOK symbols generated according to the thirteenth embodiment as illustrated in Figures 33A and 33B. As a result, transmission efficiency of the data field 340 modulated by bipolar OOK with Manchester code according to the fourteenth embodiment or the fifteenth embodiment is improved compared with the thirteenth embodiment.
In case of TGI = TLGI, the symbol period of the Manchester coded bipolar OOK symbols generated according to the fourteen embodiment or the fifteenth embodiment of the present disclosure is the same as the symbol period of the Manchester coded bipolar OOK symbols generated according to the thirteenth embodiment as illustrated in Figures 33A and 33B. As a result, transmission efficiency of the data field 340 modulated by bipolar OOK with Manchester code according to the fourteen embodiment or the fifteenth embodiment is the same as the thirteenth embodiment, but has better delay tolerance than the latter since a shorter GI is used in the latter.
Figure 36 illustrates example Manchester coded unipolar OOK symbols for the information sequence "1101010011101" generated according to the first embodiment or the second embodiment of the present disclosure. Note that the GI is not shown in Figure 36, which is configured differently according to the first embodiment and the second embodiment.
Figure 37 illustrates example Manchester coded bipolar OOK symbols for the information sequence "1101010011101" generated according to any of the eleventh embodiment to the fifteenth embodiment. Note that the GI is not shown in Figure 37, which is configured differently according to the eleventh embodiment to the fifteenth embodiment.
It can be observed from Figures 36 and 37 that compared with the Manchester coded unipolar OOK symbols, the DC (direct current) component, which is an average amplitude value of a symbol sequence, decreases in the Manchester coded bipolar OOK symbols.
<Sixteenth Embodiment>
According to a sixteenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol and an OFF sub-symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to a sixteenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol and an OFF sub-symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the sixteenth embodiment, the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is inverted from the polarity of the ON sub-symbol in the preceding Manchester coded bipolar OOK symbol if the spacing between them is equal to or larger than a threshold, high frequency component of the Manchester coded bipolar OOK symbols will be decreased.
<Seventeenth Embodiment>
According to a seventeenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that is placed at the beginning of the Manchester coded bipolar OOK symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding the term of the GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to a seventeenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that is placed at the beginning of the Manchester coded bipolar OOK symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding the term of the GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the seventeenth embodiment, the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is inverted from the polarity of the ON sub-symbol in the preceding Manchester coded bipolar OOK symbol if the spacing between them excluding the GI is equal to or larger than a threshold, high frequency component of the Manchester coded bipolar OOK symbols will be decreased.
<Eighteenth Embodiment>
According to an eighteenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and two short GIs that are placed in front of the ON sub-symbol and the OFF sub-symbol respectively. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding the term of the short GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to an eighteenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and two short GIs that are placed in front of the ON sub-symbol and the OFF sub-symbol respectively. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding the term of the short GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the eighteenth embodiment, the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is inverted from the polarity of the ON sub-symbol in the preceding Manchester coded bipolar OOK symbol if the spacing between them excluding the short GI is equal to or larger than a threshold, high frequency component of the Manchester coded bipolar OOK symbols will be decreased.
<Nineteenth Embodiment>
According to a nineteenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that is placed after the ON sub-symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding ther of the GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to a nineteenth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that is placed after the ON sub-symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding ther of the GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the nineteenth embodiment, the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is inverted from the polarity of the ON sub-symbol in the preceding Manchester coded bipolar OOK symbol if the spacing between them excluding the GI is equal to or larger than a threshold, high frequency component of the Manchester coded bipolar OOK symbols will be decreased.
<Twentieth Embodiment>
According to a twentieth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that contains no signal and that is placed at the end of the Manchester coded bipolar OOK symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding the term of the GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to a twentieth embodiment of the present disclosure, a Manchester coded bipolar OOK symbol comprises a positive or negative ON sub-symbol, an OFF sub-symbol and a GI that contains no signal and that is placed at the end of the Manchester coded bipolar OOK symbol. The polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the spacing between the two ON sub-symbols excluding the term of the GI is equal to or larger than a threshold (e.g., Tss). Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the twentieth embodiment, the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is inverted from the polarity of the ON sub-symbol in the preceding Manchester coded bipolar OOK symbol if the spacing between them excluding the term of the GI is equal to or larger than a threshold, high frequency component of the Manchester coded bipolar OOK symbols will be decreased.
<Example Waveforms>
Figure 38A illustrates an example waveform for the information sequence "1101010011101" modulated by bipolar OOK with Manchester code according to any of the sixteenth embodiment to the twentieth embodiment of the present disclosure with the threshold equal to Tss. Figure 38B illustrates another example waveform for the information sequence "1101010011101" modulated by bipolar OOK with Manchester code according to any of the sixteenth embodiment to the twentieth embodiment of the present disclosure with the threshold equal to 2×Tss. Note that the GI is not shown in Figure 38A and Figure 38B, which is configured differently according to the sixteenth embodiment to the Twentieth embodiment.
Figure 38A illustrates an example waveform for the information sequence "1101010011101" modulated by bipolar OOK with Manchester code according to any of the sixteenth embodiment to the twentieth embodiment of the present disclosure with the threshold equal to Tss. Figure 38B illustrates another example waveform for the information sequence "1101010011101" modulated by bipolar OOK with Manchester code according to any of the sixteenth embodiment to the twentieth embodiment of the present disclosure with the threshold equal to 2×Tss. Note that the GI is not shown in Figure 38A and Figure 38B, which is configured differently according to the sixteenth embodiment to the Twentieth embodiment.
It can be observed from Figures 36, 37, 38A and 38B that the Manchester coded bipolar OOK symbols generated according to any of the sixteenth embodiment to the twetieth embodiment have less high frequency component or occupy narrower bandwidth. This causes less adjacent channel interference than the Manchester coded bipolar OOK symbols generated according to any of the eleventh embodiment to the fifteenth embodiment and the Manchester coded unipolar OOK symbols generated according to the first embodiment or the second embodiment.
In addition, if the wake-up signal and the IEEE 802.11ax signal are concurrently transmitted in an OFDMA (Orthogonal Frequency Division Multiple Access) PPDU (PHY Protocol Data Unit), the Manchester coded bipolar OOK symbols generated according to any of the sixteenth embodiment to the twetieth embodiment cause less interference from/to the IEEE 802.11ax signal than the Manchester coded bipolar OOK symbols generated according to any of the eleventh embodiment to the fifteenth embodiment and the Manchester coded unipolar OOK symbols generated according to the first embodiment or the second embodiment.
According to the sixteen embodiment to the twentieth embodiment, in case that the threshold is equal to Tss, the polarity of the ON sub-symbol in a Manchester coded bipolar OOK symbol is inverted from the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol if the information of the Manchester coded bipolar OOK symbol is "1" or if the information of the Manchester coded bipolar OOK symbol is "0" and the information of the preceding Manchester coded bipolar OOK symbol is also "0". Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the sixteen embodiment to the twentieth embodiment, in case that the threshold is equal to 2×Tss, the polarity of the ON sub-symbol in a Manchester coded bipolar OOK symbol that has a preceding Manchester coded bipolar OOK symbol having an ON sub-symbol therein is inverted from positive to negative or negative to positive, if the information of the Manchester coded bipolar OOK symbol is "1" and the information of the preceding Manchester coded bipolar OOK symbol is "0". Otherwise the polarity of the ON sub-symbol in the Manchester coded bipolar OOK symbol remains unchanged and is the same as the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
According to the sixteen embodiment to the twentieth embodiment, in case that the threshold is equal to zero, the polarity of the ON sub-symbol in a Manchester coded bipolar OOK symbol is inverted from the ON sub-symbol of the preceding Manchester coded bipolar OOK symbol.
<Bipolar OOK with Symbol Repetition>
Next, bipolar OOK with symbol repetition is described herewith.
Next, bipolar OOK with symbol repetition is described herewith.
<Twenty First Embodiment>
According to a twenty first embodiment of the present disclosure, at first, an information sequence is modulated by bipolar OOK with Manchester code according to any of the eleventh embodiment to the twentieth embodiment. Then bipolar OOK symbol repetitions for the information sequence are constructed by simply repeating each Manchester coded bipolar OOK symbol twice.
According to a twenty first embodiment of the present disclosure, at first, an information sequence is modulated by bipolar OOK with Manchester code according to any of the eleventh embodiment to the twentieth embodiment. Then bipolar OOK symbol repetitions for the information sequence are constructed by simply repeating each Manchester coded bipolar OOK symbol twice.
Figures 39A and 39B illustrate example bipolar OOK symbol repetitions generated according to the twenty-first embodiment where the Manchester coded bipolar OOK symbols are generated according to the fourteen embodiment.
According to the twenty first embodiment, compared with the corresponding Manchester coded bipolar OOK symbols, the bipolar OOK symbol repetitions have a lower data rate. With the same transmit power, the bipolar OOK symbol repetitions have a longer transmission range than the corresponding Manchester coded bipolar OOK symbols.
<Twenty-second Embodiment>
According to a twenty-second embodiment of the present disclosure, the bipolar OOK symbol repetition for adjacent information "0" or "1" is constructed by concatenating the bipolar OOK symbol for adjacent information "0" and the bipolar OOK symbol for adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment. The pattern of concatenating the bipolar OOK symbols for adjacent information "0" and "1" is different between the bipolar OOK symbol repetitions for adjacent information "0" and "1". For example, for bipolar OOK symbol repetition for adjacent information "0", the bipolar OOK symbol for adjacent information "0" is before the bipolar OOK symbol for adjacent information "1"; while for bipolar OOK symbol repetition for adjacent information "1", the bipolar OOK symbol for adjacent information "1" is before the bipolar OOK symbol for adjacent information "0". Similarly, the bipolar OOK symbol repetition for non-adjacent information "0" or "1" is constructed by concatenating the bipolar OOK symbol for non-adjacent information "0" and the bipolar OOK symbol for non-adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment.
According to a twenty-second embodiment of the present disclosure, the bipolar OOK symbol repetition for adjacent information "0" or "1" is constructed by concatenating the bipolar OOK symbol for adjacent information "0" and the bipolar OOK symbol for adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment. The pattern of concatenating the bipolar OOK symbols for adjacent information "0" and "1" is different between the bipolar OOK symbol repetitions for adjacent information "0" and "1". For example, for bipolar OOK symbol repetition for adjacent information "0", the bipolar OOK symbol for adjacent information "0" is before the bipolar OOK symbol for adjacent information "1"; while for bipolar OOK symbol repetition for adjacent information "1", the bipolar OOK symbol for adjacent information "1" is before the bipolar OOK symbol for adjacent information "0". Similarly, the bipolar OOK symbol repetition for non-adjacent information "0" or "1" is constructed by concatenating the bipolar OOK symbol for non-adjacent information "0" and the bipolar OOK symbol for non-adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment.
Figures 40A and 40B illustrate example bipolar OOK symbol repetitions generated according to the twenty-second embodiment where the Manchester coded bipolar OOK symbols are generated according to the fourteen embodiment.
According to the twenty second embodiment, compared with the corresponding Manchester coded bipolar OOK symbols, the bipolar OOK symbol repetitions have a lower data rate. With the same transmit power, the bipolar OOK symbol repetitions have a longer transmission range than the corresponding Manchester coded bipolar OOK symbols.
According to the twenty-first embodiment or the twenty-second embodiment, each bipolar OOK symbol repetition comprises two positive ON sub-symbols or two negative ON sub-symbols. The DC component of the bipolar OOK symbol repetitions generated according to the twenty-first embodiment or the twenty-second embodiment may be significant.
<Twenty-third Embodiment>
According to a twenty-third embodiment of the present disclosure, the bipolar OOK symbol repetition for adjacent or non-adjacent information "0" (or "1") is constructed by concatenating the bipolar OOK symbol for adjacent and non-adjacent information "0" (or "1") according to any of the eleventh embodiment to the fifteenth embodiment. The pattern of concatenating the bipolar OOK symbols for adjacent and non-adjacent information "0" (or "1") is different between the bipolar OOK symbol repetitions for adjacent information "0" and non-adjacent information "0" (or "1"). For example, for bipolar OOK symbol repetition for adjacent information "0", the bipolar OOK symbol for adjacent information "0" is before the bipolar OOK symbol for non-adjacent information "0"; while for bipolar OOK symbol repetition for non-adjacent information "0", the bipolar OOK symbol for non-adjacent information "0" is before the bipolar OOK symbol for adjacent information "0".
According to a twenty-third embodiment of the present disclosure, the bipolar OOK symbol repetition for adjacent or non-adjacent information "0" (or "1") is constructed by concatenating the bipolar OOK symbol for adjacent and non-adjacent information "0" (or "1") according to any of the eleventh embodiment to the fifteenth embodiment. The pattern of concatenating the bipolar OOK symbols for adjacent and non-adjacent information "0" (or "1") is different between the bipolar OOK symbol repetitions for adjacent information "0" and non-adjacent information "0" (or "1"). For example, for bipolar OOK symbol repetition for adjacent information "0", the bipolar OOK symbol for adjacent information "0" is before the bipolar OOK symbol for non-adjacent information "0"; while for bipolar OOK symbol repetition for non-adjacent information "0", the bipolar OOK symbol for non-adjacent information "0" is before the bipolar OOK symbol for adjacent information "0".
Figures 41A and 41B illustrate example bipolar OOK symbol repetitions generated according to the twenty-third embodiment where the Manchester coded bipolar OOK symbols are generated according to the fourteen embodiment.
According to the twenty-third embodiment, the DC component of the bipolar OOK symbol repetitions will be decreased.
<Twenty-fourth Embodiment>
According to a twenty-fourth embodiment of the present disclosure, the bipolar OOK symbol repetition for adjacent information "0" or non-adjacent information "1" is constructed by concatenating a bipolar OOK symbol for adjacent information "0" and a bipolar OOK symbol for non-adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment. The pattern of concatenating the bipolar OOK symbols for adjacent information "0" and non-adjacent information "1" is different between the bipolar OOK symbol repetitions for adjacent information "0" and non-adjacent information "1". For example, for bipolar OOK symbol repetition for adjacent information "0", the bipolar OOK symbol for adjacent information "0" is placed before the bipolar OOK symbol for non-adjacent information "1"; while for bipolar OOK symbol repetition for non-adjacent information "1", the bipolar OOK symbol for non-adjacent information "1" is placed before the bipolar OOK symbol for adjacent information "0". The bipolar OOK symbol repetition for non-adjacent information "0" or adjacent information "1" is constructed by concatenating a bipolar OOK symbol for non-adjacent information "0" and a bipolar OOK symbol for adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment. Figures 42A and 42B illustrate example bipolar OOK symbol repetitions generated according to the twenty-fourth embodiment where the Manchester coded bipolar OOK symbols are generated according to the fourteen embodiment.
According to a twenty-fourth embodiment of the present disclosure, the bipolar OOK symbol repetition for adjacent information "0" or non-adjacent information "1" is constructed by concatenating a bipolar OOK symbol for adjacent information "0" and a bipolar OOK symbol for non-adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment. The pattern of concatenating the bipolar OOK symbols for adjacent information "0" and non-adjacent information "1" is different between the bipolar OOK symbol repetitions for adjacent information "0" and non-adjacent information "1". For example, for bipolar OOK symbol repetition for adjacent information "0", the bipolar OOK symbol for adjacent information "0" is placed before the bipolar OOK symbol for non-adjacent information "1"; while for bipolar OOK symbol repetition for non-adjacent information "1", the bipolar OOK symbol for non-adjacent information "1" is placed before the bipolar OOK symbol for adjacent information "0". The bipolar OOK symbol repetition for non-adjacent information "0" or adjacent information "1" is constructed by concatenating a bipolar OOK symbol for non-adjacent information "0" and a bipolar OOK symbol for adjacent information "1" according to any of the eleventh embodiment to the fifteenth embodiment. Figures 42A and 42B illustrate example bipolar OOK symbol repetitions generated according to the twenty-fourth embodiment where the Manchester coded bipolar OOK symbols are generated according to the fourteen embodiment.
According to the twenty-third embodiment or the twenty-fourth embodiment, each bipolar OOK symbol repetition comprises a positive ON sub-symbol and a negative ON sub-symbol. According to the twenty-third embodiment or the twenty-fourth embodiment, the DC component of the bipolar OOK symbol repetitions decreases compared to those generated according to the twenty-first embodiment or the twenty-second embodiment.
<Summary>
According to the present disclosure, thedata field 340 of the wake-up packet 300 can be modulated by unipolar OOK with Manchester code, bipolar OOK with Manchester code, unipolar OOK with symbol repetition or bipolar OOK with symbol repetition. Unipolar OOK with Manchester code can be performed according to the first embodiment or the second embodiment. Unipolar OOK with symbol repetition can be performed according to any of the third embodiment to the eighth embodiment. Bipolar OOK with Manchester code can be performed according to any of the eleventh embodiment to the twentieth embodiment. Bipolar OOK with symbol repetition can be performed according to any of the twenty-first embodiment to the twenty-fourth embodiment.
According to the present disclosure, the
According to the present disclosure, which scheme is used to modulate the data field 340 of the wake-up packet 300 depends on transmission range requirement. For example, since the bipolar or unipolar OOK with symbol repetition has a lower data rate than the bipolar or unipolar OOK with Manchester code, with the same transmit power, the former has a longer transmission range than the latter. In other word, the bipolar or lunipolar OOK with symbol repetition is more suitable for extened range transmission than the bipolar or unipolar OOK with Manchester code.
According to any previous embodiment of the present disclosure, various spread spectrum based methods may be used to generate the ON sub-symbol or the useful portion of the ON symbol for the purpose of achieving better resistence to multipath fading. Example spread spectrum based methods include
- CSS (Chirp Spread Spectrum) which has been used in the IEEE 802.15.4a;
- DSSS (Direct Sequence Spread Spectrum) with Barker code which has been used in the IEEE 802.11b;
- DFT-spread OFDM with Zadoff-Chu sequence which has been used in the LTE (Long-Term Evolution) uplink; and
- Multicarrier OOK.
- CSS (Chirp Spread Spectrum) which has been used in the IEEE 802.15.4a;
- DSSS (Direct Sequence Spread Spectrum) with Barker code which has been used in the IEEE 802.11b;
- DFT-spread OFDM with Zadoff-Chu sequence which has been used in the LTE (Long-Term Evolution) uplink; and
- Multicarrier OOK.
The present disclosure can be realized by software, hardware, or software in cooperation with hardware. Each functional block used in the description of each embodiment described above can be partly or entirely realized by an LSI such as an integrated circuit, and each process described in the each embodiment may be controlled partly or entirely by the same LSI or a combination of LSIs. The LSI may be individually formed as chips, or one chip may be formed so as to include a part or all of the functional blocks. The LSI may include a data input and output coupled thereto. The LSI here may be referred to as an IC, a system LSI, a super LSI, or an ultra LSI depending on a difference in the degree of integration. However, the technique of implementing an integrated circuit is not limited to the LSI and may be realized by using a dedicated circuit, a general-purpose processor, or a special-purpose processor. In addition, a FPGA (Field Programmable Gate Array) that can be programmed after the manufacture of the LSI or a reconfigurable processor in which the connections and the settings of circuit cells disposed inside the LSI can be reconfigured may be used. The present disclosure can be realized as digital processing or analogue processing, as a result of the advancement of semiconductor technology or other derivative technology,
Should a circuit integration technology replacing LSI appear as a result of advancements in semiconductor technology or other technologies derived from the technology, the functional blocks could be integrated using the future integrated circuit technology. Another possibility is the application of biotechnology and/or the like.
This disclosure can be applied to an apparatus and a method for transmitting a wake-up signal in a wireless network.
110, 210 AP
120, 130, 140, 220, 230, 240 STA
112, 122, 132, 142, 212, 222, 232, 242, 2700 PCR
134, 144, 214, 234, 244, 2500, 2900 WUR
2720 Transmitter
2510 Receiver
2920 Transceiver
2710, 2910 Wake-up signal generator
2520, 2930 Wake-up signal processing circuitry
2630, 2810, 3010 MAC processing circuitry
2610, 2830, 3040 RF & analog front-end circuitry
2822, 3022 Legacy preamble generation circuitry
2824, 3024 Wake-up preamble generation circuitry
2826, 3026 OOK waveform generation circuitry
2626, 2828, 3028 Coding control circuitry
2622, 3030 Payload detection & synchronization circuitry
2624, 3032 OOK detection circuitry
120, 130, 140, 220, 230, 240 STA
112, 122, 132, 142, 212, 222, 232, 242, 2700 PCR
134, 144, 214, 234, 244, 2500, 2900 WUR
2720 Transmitter
2510 Receiver
2920 Transceiver
2710, 2910 Wake-up signal generator
2520, 2930 Wake-up signal processing circuitry
2630, 2810, 3010 MAC processing circuitry
2610, 2830, 3040 RF & analog front-end circuitry
2822, 3022 Legacy preamble generation circuitry
2824, 3024 Wake-up preamble generation circuitry
2826, 3026 OOK waveform generation circuitry
2626, 2828, 3028 Coding control circuitry
2622, 3030 Payload detection & synchronization circuitry
2624, 3032 OOK detection circuitry
Claims (15)
- A communication apparatus comprising:
a transmission signal generator which, in operation, generates a transmission signal that includes a legacy preamble, a non-legacy preamble and a data field for a wake-up signal, wherein the data field is modulated by On-Off Keying (OOK) with Manchester code or OOK with symbol repetition; wherein a Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a guard interval (GI) that is placed after the ON sub-symbol; and
a transmitter which, in operation, transmits the generated transmission signal. - The communication apparatus according to claim 1, wherein
the GI is a cyclic postfix of the ON sub-symbol of the Manchester coded OOK symbol or the GI contains no signal. - The communication apparatus according to claim 1, wherein
the GI follows the ON sub-symbol of the Manchester coded OOK symbol. - The communication apparatus according to claim 1, wherein
the GI is placed at the end of the Manchester coded OOK symbol. - The communication apparatus according to claim 1, wherein
an OOK symbol repetition comprises the useful portion of an ON symbol, the useful portion of an OFF symbol and a GI that is placed after the useful portion of the ON symbol. - The communication apparatus according to claim 5, wherein
the GI is a cyclic postfix of the useful portion of the ON symbol of the OOK symbol repetition or the GI contains no signal. - The communication apparatus according to claim 5, wherein
the GI follows the useful portion of the ON symbol of the OOK symbol repetition. - The communication apparatus according to claim 5, wherein
the GI is placed at the end of the OOK symbol repetition. - The communication apparatus according to claim 1, wherein
an OOK symbol repetition comprises a first OOK symbol and a second OOK symbol, either of the first OOK symbol and the second OOK symbols comprising of an ON sub-symbol, an OFF sub-symbol and a GI that is placed after the ON sub-symbol. - The communication apparatus according to claim 9, wherein
the GI is a cyclic postfix of the ON sub-symbol of the OOK symbol or the GI contains no signal. - The communication apparatus according to claim 9, wherein
the GI follows after the ON sub-symbol of the OOK symbol. - The communication apparatus according to claim 9, wherein
the GI is placed at the end of the OOK symbol. - The communication apparatus according to claim 9, wherein
both the first OOK symbol and the second OOK symbol correspond to the same information. - The communication apparatus according to claim 9, wherein
both the first OOK symbol and the second OOK symbol correspond to different information. - A communication method comprising:
generating a transmission signal that includes a legacy preamble, a non-legacy preamble and a data field for a wake-up signal, wherein the data field is modulated by On-Off Keying (OOK) with Manchester code or OOK with symbol repetition and wherein a Manchester coded OOK symbol comprises an ON sub-symbol, an OFF sub-symbol and a guard interval (GI) that is placed after the ON sub-symbol; and
transmitting the generated transmission signal.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| US11671297B2 (en) | 2018-10-11 | 2023-06-06 | Sony Group Corporation | Orthogonal frequency division multiplex and non-coherent demodulation |
-
2018
- 2018-02-13 WO PCT/JP2018/004780 patent/WO2018163718A1/en active Application Filing
Non-Patent Citations (3)
| Title |
|---|
| LEE, K. ET AL.: "The Chaotic On-off Keying with Guard Interval for Ultra-Wideband Communication", IEEE VTS ASIA PACIFIC WIRELESS COMMUNICATIONS SYMPOSIUM, August 2006 (2006-08-01) * |
| PARK, E. ET AL.: "Further Investigation on WUR Performance", IEEE 802.11-16/1144R0, September 2016 (2016-09-01), XP068107537, Retrieved from the Internet <URL:https://mentor.ieee.org/802.11/dcn/16/11-16-1144-00-Owur-further-investigation-on-wur-performance.ppt> [retrieved on 20180420] * |
| PARK, M. ET AL.: "LP-WUR (Low- Power Wake-Up Receiver) Follow-Up", IEEE 802.11-16/ 0341R0, March 2016 (2016-03-01), XP055471802, Retrieved from the Internet <URL:https://mentor.ieee.org/802.11/dcn/16/11-16-0341-00-lrlp-low-power-wake-up-receiver-follow-up.pptx> [retrieved on 20180420] * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11671297B2 (en) | 2018-10-11 | 2023-06-06 | Sony Group Corporation | Orthogonal frequency division multiplex and non-coherent demodulation |
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