TWI653862B - Dual subcarrier modulation method and wireless station - Google Patents

Dual subcarrier modulation method and wireless station Download PDF

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TWI653862B
TWI653862B TW107103660A TW107103660A TWI653862B TW I653862 B TWI653862 B TW I653862B TW 107103660 A TW107103660 A TW 107103660A TW 107103660 A TW107103660 A TW 107103660A TW I653862 B TWI653862 B TW I653862B
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resource unit
modulation
modulation symbols
group
subcarrier
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TW107103660A
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TW201830937A (en
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蓋瑞 安威爾
劉劍函
天宇 伍
湯姆士艾德華 皮爾二世
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聯發科技股份有限公司
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/26Systems using multi-frequency codes
    • H04L27/2601Multicarrier modulation systems
    • H04L27/2614Peak power aspects
    • H04L27/2615Reduction thereof using coding
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/18Phase-modulated carrier systems, i.e. using phase-shift keying
    • H04L27/20Modulator circuits; Transmitter circuits

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)

Abstract

提供一種雙子載波調製方法,該雙子載波調製方法在高效率WLAN中引入雙子載波調製DCM。DCM可以通過在頻域分離的兩個子載波上發送相同的資訊來將頻率分集引入到OFDM系統中。如果應用DCM,則發射器將相同的編碼位元調製到具有相同或不同星座映射方案的兩個頻域分離的子載波上。DCM會受到較高的峰均功率比PAPR的影響。根據一新穎方面,提出了一種利用二進位相移鍵控的雙子載波調製DCM和較低的PAPR來發送和編碼HE PPDU訊框的方法。 A dual subcarrier modulation method is provided. The dual subcarrier modulation method introduces a dual subcarrier modulation DCM in a high-efficiency WLAN. DCM can introduce frequency diversity into an OFDM system by sending the same information on two subcarriers separated in the frequency domain. If DCM is applied, the transmitter modulates the same coded bits onto two frequency-domain separated subcarriers with the same or different constellation mapping schemes. DCM is affected by higher peak-to-average power ratio PAPR. According to a novel aspect, a method for transmitting and encoding a HE PPDU frame using a binary phase shift keyed dual subcarrier modulation DCM and a lower PAPR is proposed.

Description

雙子載波調製方法和無線站點 Dual subcarrier modulation method and wireless station

本發明涉及無線網路通信領域,特別是涉及無線通訊系統中的雙子載波調製(dual subcarrier modulation,DCM)和峰均功率比(peak-to-average power ratio,PAPR)的降低。 The present invention relates to the field of wireless network communications, and in particular, to the reduction of dual subcarrier modulation (DCM) and peak-to-average power ratio (PAPR) in wireless communication systems.

IEEE 802.11是一組用於在Wi-Fi(2.4、3.6、5和60GHz)頻帶中實現無線局域網(wireless local area network,WLAN)通信的媒體存取控制(media access control,MAC)和實體層(physical layer,PHY)的規範。802.11系列包括一系列使用同樣的基本協議的半雙工傳輸無線調製技術。標準和修訂為使用Wi-Fi頻帶的無線網路產品提供了基礎。例如,IEEE 802.11ac是IEEE 802.11系列中的無線網路標準,其提供了5G頻帶上的高輸送量的WLAN。在IEEE 802.11ac標準中提出了顯著變寬的通道頻寬(20MHz、40MHz、80MHz和160MHz)。高效WLAN研究組(High Efficiency WLAN study group,HEW SG)是IEEE 802.11工作組中的一個研究組,IEEE 802.11工作組將會考慮提升頻譜效率以提高無線裝置在高密度場景下的系統輸送量。由於HEW SG的緣故,TGax(一個IEEE任務組)成立並負責研究IEEE 802.11ax標準,該標準將成為IEEE 802.11ac的繼任標準。最近,WLAN的需求已經在許多行業的組織中呈指數級增長。 IEEE 802.11 is a set of media access control (MAC) and physical layer (MAC) for wireless local area network (WLAN) communication in the Wi-Fi (2.4, 3.6, 5 and 60 GHz) bands. physical layer (PHY). The 802.11 series includes a series of half-duplex transmission wireless modulation technologies using the same basic protocol. Standards and amendments provide the basis for wireless networking products using the Wi-Fi band. For example, IEEE 802.11ac is a wireless network standard in the IEEE 802.11 series, which provides high-throughput WLANs in the 5G frequency band. Significantly wider channel bandwidths (20MHz, 40MHz, 80MHz, and 160MHz) are proposed in the IEEE 802.11ac standard. The High Efficiency WLAN study group (HEW SG) is a research group in the IEEE 802.11 working group. The IEEE 802.11 working group will consider improving the spectral efficiency to increase the system throughput of wireless devices in high-density scenarios. Due to HEW SG, TGax (an IEEE task force) was established and is responsible for studying the IEEE 802.11ax standard, which will become the successor standard to IEEE 802.11ac. Recently, demand for WLANs has grown exponentially in organizations in many industries.

在HE WLAN中引入正交頻分多址(Orthogonal Frequency Division Multiple Access,OFDMA)以通過將子載波的子集分配給不同的用戶,允許複數個用戶同時進行資料傳輸,從而提升用戶體驗。在OFDMA中,每一個用戶被分 配一組被稱為資源單元(resource unit,RU)的子載波。在HE WLAN中,無線站點(station,STA)可以在上行和下行OFDMA中傳輸最小尺寸的RU(其大約是2MHz頻寬)。與其20MHz的前導碼相比,其資料部分的功率密度比前導碼部分高9dB。這種窄帶的上行OFDMA信號很難被CCA(Clear Channel Assessment,空閒通道檢測)檢測到,因為CCA在大於或等於20MHz的頻寬上工作。因此,一個STA在特定窄帶的子載波上可能比其他子載波多受到9dB的干擾。可以看出,窄帶干擾是HE WLAN中固有的。需要能夠處理這樣的窄帶干擾的方案。 Orthogonal Frequency Division Multiple Access (OFDMA) is introduced in HE WLAN to allocate a subset of subcarriers to different users, allowing multiple users to transmit data at the same time, thereby improving the user experience. In OFDMA, each user is divided Allocate a set of subcarriers called resource units (RUs). In HE WLAN, a wireless station (station, STA) can transmit the smallest RU (which is about 2 MHz bandwidth) in uplink and downlink OFDMA. Compared with its preamble of 20MHz, the power density of its data part is 9dB higher than that of the preamble part. Such a narrow-band uplink OFDMA signal is difficult to be detected by a CCA (Clear Channel Assessment, Clear Channel Assessment), because the CCA works on a bandwidth greater than or equal to 20 MHz. Therefore, a STA may suffer 9dB more interference on a specific narrowband subcarrier than other subcarriers. It can be seen that narrowband interference is inherent in HE WLAN. What is needed is a scheme capable of handling such narrowband interference.

在多用戶(Multi-User,MU)傳輸中,在1x符號(symbol)持續時間內對HE-SIG-B進行編碼。結果,當使用同樣的調製和編碼方案(modulation and coding scheme,MCS)時,其性能比具有4x符號(symbol)持續時間的資料符號差。HE-SIG-B需要更穩定的調製方案。此外,為了擴大室外場景的範圍,希望一種新的調製方案,新的調製方案的SNR比MCS0的SNR更低。 In Multi-User (MU) transmission, HE-SIG-B is encoded within a 1x symbol duration. As a result, when the same modulation and coding scheme (MCS) is used, its performance is worse than data symbols with a 4x symbol duration. HE-SIG-B requires a more stable modulation scheme. In addition, in order to expand the range of outdoor scenes, a new modulation scheme is desired. The SNR of the new modulation scheme is lower than that of MCS0.

雙子載波調製(Dual Sub-Carrier Modulation,DCM)在一對子載波上調製相同的資訊。DCM可以通過在頻域分離的兩個子載波上傳輸相同的資訊來將頻率分集引入到OFDM系統中。DCM可以以低複雜度實現,並提供比當前WLAN中使用的調製方案更好的性能。DCM增強了傳輸可靠性,特別是在窄帶干擾下。既可以使用二進位卷積碼(binary convolutional code,BCC)也可以使用低密度奇偶校驗(low-density parity check,LDPC)碼對HE PPDU(Presentation Protocol Data Unit,協定資料單元)的資料欄位進行編碼。通過HE PPDU的HE-SIG-A中的編碼欄位選擇編碼器。 Dual Sub-Carrier Modulation (DCM) modulates the same information on a pair of sub-carriers. DCM can introduce frequency diversity into an OFDM system by transmitting the same information on two subcarriers separated in the frequency domain. DCM can be implemented with low complexity and provides better performance than the modulation schemes used in current WLANs. DCM enhances transmission reliability, especially under narrow-band interference. You can use binary convolutional code (BCC) or low-density parity check (LDPC) code to the data field of HE PPDU (Presentation Protocol Data Unit). To encode. The encoder is selected by the encoding field in HE-SIG-A of the HE PPDU.

雖然DCM在多徑衰落通道中分集方面有顯著的改進,但會遭受高峰均功率比(peak-to-average power ratio,PAPR)的影響。尋求在DCM下降低PAPR的解決方案。 Although DCM has a significant improvement in diversity in multipath fading channels, it suffers from the impact of peak-to-average power ratio (PAPR). Find a solution to reduce PAPR under DCM.

本發明主要解決的技術問題是提供低峰均功率比雙子載波調製方法和無線站點,能夠解決窄帶干擾的問題。 The technical problem mainly solved by the invention is to provide a low peak-to-average power ratio dual subcarrier modulation method and a wireless station, which can solve the problem of narrow-band interference.

本發明一方面提供一種雙子載波調製方法,其包括:對正交頻分複用無線局域網中將由源站點通過資源單元發送到目的站點的資料資訊進行編碼;使用第一二進位相移鍵控調製方案將編碼的位元調製為第一組調製符號,其中所述第一組調製符號被映射到所述資源單元的第一部分的子載波上;如果採用雙載波調製,則使用第二二進位相移鍵控調製方案將同樣的所述編碼的位元調製為第二組調製符號,其中所述第二組調製符號被映射到所述資源單元的第二部分的子載波上;將包含所述第一組調製符號和/或所述第二組調製符號的資料包傳輸給所述目的站點。 One aspect of the present invention provides a dual subcarrier modulation method, which includes: encoding data information transmitted from a source site to a destination site through a resource unit in an Orthogonal Frequency Division Multiplexing wireless local area network; using a first binary phase shift The keyed modulation scheme modulates the coded bits into a first set of modulation symbols, where the first set of modulation symbols are mapped onto the subcarriers of the first part of the resource unit; if dual carrier modulation is used, the second bit is used The binary phase shift keying modulation scheme modulates the same coded bits into a second group of modulation symbols, where the second group of modulation symbols is mapped onto a subcarrier of a second part of the resource unit; A data packet containing the first group of modulation symbols and / or the second group of modulation symbols is transmitted to the destination station.

本發明一方面提供一種無線站點,其包括:編碼器,對正交頻分複用無線局域網中將由源站點通過資源單元發送到目的站點的資料資訊進行編碼;調製器,使用第一二進位相移鍵控調製方案將編碼的位元調製為第一組調製符號,其中所述第一組調製符號被映射到所述資源單元的第一部分的子載波上;如果採用雙載波調製,則所述調製器使用第二二進位相移鍵控調製方案將同樣的所述編碼的位元調製為第二組調製符號,其中所述第二組調製符號被映射到所述資源單元的第二部分的子載波上;以及傳輸器,將包含所述第一組調製符號和/或所述第二組調製符號的資料包傳輸給所述目的站點。 One aspect of the present invention provides a wireless station, which includes: an encoder that encodes data information to be transmitted from a source site to a destination site through a resource unit in an orthogonal frequency division multiplexed wireless local area network; a modulator that uses a first The binary phase shift keying modulation scheme modulates the coded bits into a first set of modulation symbols, where the first set of modulation symbols is mapped onto the subcarriers of the first part of the resource unit; if dual carrier modulation is used, Then the modulator uses a second binary phase shift keying modulation scheme to modulate the same coded bits into a second set of modulation symbols, where the second set of modulation symbols are mapped to the first Two subcarriers; and a transmitter, transmitting the data packet containing the first group of modulation symbols and / or the second group of modulation symbols to the destination station.

其中,所述資源單元的第一部分是所述資源單元的第一半頻段;所述資源單元的第二部分是所述資源單元的第二半頻段,其中,所述資源單元的第一半頻段是所述資源單元的上半頻段和所述資源單元的下半頻段中的其中一個;所述資源單元的第二半頻段是所述資源單元的上半頻段和所述資源單元的下半頻段中的另一個。 The first part of the resource unit is the first half-band of the resource unit; the second part of the resource unit is the second half-band of the resource unit, and the first half-band of the resource unit Is one of the upper half frequency band of the resource unit and the lower half frequency band of the resource unit; the second half frequency band of the resource unit is the upper half frequency band of the resource unit and the lower half frequency band of the resource unit The other one.

在高效率(high efficiency,HE)WLAN中引入雙子載波調製(Dual sub-carrier modulation,DCM)。DCM是處理窄帶干擾和範圍擴展的解決方案。DCM可以通過在頻域分離的兩個子載波上發送相同的資訊來將頻率分集引入到OFDM系統中。如果應用DCM,則發射器使用相同或不同星座映射方案,將相同的編碼位元調製到兩個頻域分離的子載波上。DCM會受到較高的峰均功率比(peak-to-average power ratio,PAPR)的影響。根據一個方面,提出了一種利用二進位相移鍵控(binary phase shift keying,BPSK)DCM和較低的PAPR來發送和編碼HE PPDU訊框的方法。在一個實施例中,第一BPSK調製方案被用於將資料包中的編碼位元映射到下半頻段的子載波上;第二BPSK調製方案被用於將資料包中的相同的編碼位元映射到上半頻段的子載波上,其中上半頻段的子載波的頻率比下半頻段的子載波的頻率高或者比下半頻段的子載波的頻率低。設計第一和第二BPSK調製方案以實現低PAPR。在一個示例中,第一組調製符號由sn表示,第二組調製符號由sm表示,其中n和m是子載波索引,並且sm=sn*ej*(pi)*m。 Introducing Dual Subcarrier Modulation in High Efficiency (HE) WLAN sub-carrier modulation (DCM). DCM is a solution for narrow-band interference and range extension. DCM can introduce frequency diversity into an OFDM system by sending the same information on two subcarriers separated in the frequency domain. If DCM is applied, the transmitter uses the same or different constellation mapping schemes to modulate the same coded bits onto two frequency-domain separated subcarriers. DCM is affected by a higher peak-to-average power ratio (PAPR). According to one aspect, a method is proposed for transmitting and encoding HE PPDU frames using binary phase shift keying (BPSK) DCM and lower PAPR. In one embodiment, the first BPSK modulation scheme is used to map the coded bits in the data packet to the subcarriers in the lower half of the frequency band; the second BPSK modulation scheme is used to map the same coded bits in the data packet Map to the sub-carriers in the upper half-band, where the frequency of the sub-carriers in the upper half-band is higher than the frequency of the sub-carriers in the lower half-band or lower than the frequency of the sub-carriers in the lower half-band. Design the first and second BPSK modulation schemes to achieve low PAPR. In one example, the first group of modulation symbols is represented by sn, and the second group of modulation symbols is represented by sm, where n and m are subcarrier indexes, and sm = sn * ej * (pi) * m.

在一個實施例中,無線的源站點在正交頻分複用(orthogonal frequency division multiplexing,OFDM)無線局域網中通過資源單元(RU)對將從源站點傳輸到目的站點的資料資訊進行編碼。源站點使用第一BPSK調製方案將編碼的位元調製為第一組調製符號,其中第一組調製符號被映射到RU的第一半頻段的子載波上,其中RU的第一半頻段可以是RU的上半頻段和RU的下半頻段中其中一個。如果應用雙子載波調製(DCM),則源站點使用第二BPSK調製方案將相同的編碼的位元調製為第二組調製符號,其中第二組調製符號被映射到RU的第二半頻段的子載波上,其中RU的第二半頻段可以是RU的上半頻段和RU的下半頻段中另一個。源站點將包含第一組調製符號和/或第二組調製符號的資料包發送到目的站點。 In one embodiment, the wireless source site performs resource information (RU) on the material information transmitted from the source site to the destination site in an orthogonal frequency division multiplexing (OFDM) wireless local area network. coding. The source site uses the first BPSK modulation scheme to modulate the coded bits into a first set of modulation symbols, where the first set of modulation symbols is mapped onto the first half-band subcarrier of the RU, where the first half-band of the RU can be It is one of the upper half of the RU and the lower half of the RU. If dual subcarrier modulation (DCM) is applied, the source site uses the second BPSK modulation scheme to modulate the same coded bits into a second set of modulation symbols, where the second set of modulation symbols is mapped to the second half of the RU On the subcarriers, the second half frequency band of the RU may be the other of the upper half frequency band of the RU and the lower half frequency band of the RU. The source station sends a data packet containing the first group of modulation symbols and / or the second group of modulation symbols to the destination station.

本發明通過使用第一BPSK調製方案將資料包中的編碼位元映射到 資源單元的第一部分的子載波,使用第二BPSK調製方案將資料包中的相同的編碼位元映射到資源單元的第二部分的子載波,即將相同的編碼位元映射到不同子載波上,這樣在窄帶干擾的時候,可以選擇具有較好SNR的子載波上的信號進行後續計算和處理,因此能有效的解決窄帶干擾的問題。 The present invention uses the first BPSK modulation scheme to map the encoded bits in the data packet to The subcarriers in the first part of the resource unit use the second BPSK modulation scheme to map the same coding bits in the data packet to the subcarriers in the second part of the resource unit, that is, the same coding bits are mapped to different subcarriers. In this way, in the case of narrow-band interference, signals on subcarriers with better SNR can be selected for subsequent calculation and processing, so the problem of narrow-band interference can be effectively solved.

其他實施例和優點在下面的詳細描述中進行描述。本發明內容不用於限定本發明。 Other embodiments and advantages are described in the following detailed description. This summary is not intended to limit the invention.

100‧‧‧無線通訊系統 100‧‧‧Wireless communication system

101‧‧‧接入點 101‧‧‧ access point

102‧‧‧無線站點 102‧‧‧Wireless Site

110‧‧‧HE PPDU訊框 110‧‧‧HE PPDU frame

111‧‧‧常規短訓練欄位 111‧‧‧ Regular short training field

112‧‧‧常規長訓練欄位 112‧‧‧ Regular training field

113‧‧‧常規信令欄位 113‧‧‧General Signaling Field

114‧‧‧重複常規信令欄位 114‧‧‧ Repeat regular signalling field

115‧‧‧高效信令A欄位 115‧‧‧ Efficient Signaling Field A

116‧‧‧高效信令B欄位 116‧‧‧Efficient Signaling B Field

117‧‧‧高效短訓練欄位 117‧‧‧Efficient short training field

118,119‧‧‧高效長訓練欄位 118,119‧‧‧Highly efficient training field

120‧‧‧資料載荷 120‧‧‧Data payload

121‧‧‧資料包擴展 121‧‧‧Package Expansion

200‧‧‧通信系統 200‧‧‧communication system

201,211‧‧‧無線裝置 201, 211‧‧‧ wireless devices

207,208,217,218‧‧‧天線 207,208,217,218‧‧‧antenna

205‧‧‧編碼器 205‧‧‧ Encoder

204‧‧‧符號映射器/調製器 204‧‧‧Symbol Mapper / Modulator

206,216‧‧‧RF收發模組 206, 216‧‧‧RF transceiver module

203,213‧‧‧處理器 203, 213‧‧‧ processors

202,212‧‧‧記憶體 202, 212‧‧‧Memory

210,220‧‧‧程式指令和資料 210, 220‧‧‧ program instructions and information

209,219‧‧‧OFDMA模組 209,219‧‧‧OFDMA module

215‧‧‧解碼器 215‧‧‧ decoder

214‧‧‧符號解映射器/解調制器 214‧‧‧Symbol demapper / demodulator

300‧‧‧傳輸裝置 300‧‧‧Transmission device

301‧‧‧編碼器/交織器 301‧‧‧ Encoder / Interleaver

302‧‧‧DCM映射器 302‧‧‧DCM Mapper

303‧‧‧IFFT 303‧‧‧IFFT

400‧‧‧資源單元 400‧‧‧ resource unit

600‧‧‧接收裝置 600‧‧‧ receiving device

601‧‧‧FFT 601‧‧‧FFT

602‧‧‧解映射器/解調器 602‧‧‧Demapper / Demodulator

603‧‧‧解碼器 603‧‧‧ decoder

第1圖是根據一方面的支援具有降低的PAPR的DCM傳輸的無線通訊系統和HE PPDU訊框結構;第2圖是根據一方面的無線裝置的簡化框圖;第3圖是根據一方面的應用雙子載波調製的傳輸裝置的簡化示意圖;第4圖是用於具有降低峰均功率比(peak-to-average power ratio,PAPR)的DCM的BPSK調製映射方案的示例;第5圖是對應於不同的BPSK調製方案的PAPR的累積分佈函數(cumulative distribution function,CDF))的示例;第6圖是應用DCM解調和解映射的接收裝置的簡化示意圖;第7圖是根據一方面的使用DCM和降低的PAPR傳輸並且編碼HE PPDU訊框的方法流程圖。 Figure 1 is a wireless communication system and HE PPDU frame structure supporting DCM transmission with reduced PAPR according to one aspect; Figure 2 is a simplified block diagram of a wireless device according to one aspect; Figure 3 is according to one aspect Simplified schematic diagram of a transmission device using dual subcarrier modulation; Figure 4 is an example of a BPSK modulation mapping scheme for DCM with reduced peak-to-average power ratio (PAPR); Figure 5 is the corresponding Examples of the cumulative distribution function (CDF) of PAPR for different BPSK modulation schemes; Figure 6 is a simplified schematic diagram of a receiving device using DCM demodulation and demapping; Figure 7 is the use of DCM according to one aspect A flowchart of a method for transmitting and encoding HE PPDU frames with reduced PAPR.

現在將詳細參考本發明的一些實施例,其示例在附圖中示出。 Reference will now be made in detail to some embodiments of the invention, examples of which are illustrated in the accompanying drawings.

第1圖是根據一方面的支援具有降低的PAPR(peak-to-average power ratio,峰均功率比)的DCM(dual carrier modulation,雙載波調製)傳輸的無線通訊 系統100和高效率HE PPDU訊框結構。無線通訊網路100包括無線接入點AP101和無線站點STA102。在無線通訊系統中,無線裝置通過各種明確定義的訊框結構相互之間進行通信。訊框包括實體層收斂程式(Physical Layer Convergence Procedure,PLCP)協定資料單元(PPDU)、訊框頭和有效載荷。訊框依次被劃分為非常具體和標準的部分。在第1圖中,高效(high efficiency,HE)PPDU訊框110被從AP101傳輸到STA 102。HE PPDU 110包括常規短訓練欄位(legacy short training field,L-STF)111、常規長訓練欄位(legacy long training field,L-LTF)112、常規信令欄位(legacy signal field,L-SIG)113、重複常規信令欄位(repeat legacy signal field,RL-SIG)114、高效信令A欄位(HE signal A field,HE-SIG-A)115、高效信令B欄位(HE signal B field,HE-SIG-B)116、高效短訓練欄位(HE shorttraining field,HE-STF)117、用於資料的高效長訓練欄位(HE long training field,HE-LTF)118和119、高效資料載荷120和資料包擴展(Packet Extension,PE)121。 Figure 1 is a wireless communication that supports DCM (dual carrier modulation) transmission with reduced PAPR (peak-to-average power ratio). System 100 and high efficiency HE PPDU frame structure. The wireless communication network 100 includes a wireless access point AP101 and a wireless station STA102. In a wireless communication system, wireless devices communicate with each other through various well-defined frame structures. The frame includes a Physical Layer Convergence Procedure (PLCP) protocol data unit (PPDU), a frame header, and a payload. The frame is in turn divided into very specific and standard sections. In FIG. 1, a high efficiency (HE) PPDU frame 110 is transmitted from the AP 101 to the STA 102. The HE PPDU 110 includes a conventional short training field (L-STF) 111, a conventional long training field (L-LTF) 112, and a conventional signal field (L-STF). SIG) 113, Repeat legacy signal field (RL-SIG) 114, HE signal A field (HE-SIG-A) 115, and Efficient signaling B field (HE signal B field (HE-SIG-B) 116, HE short training field (HE-STF) 117, HE long training field (HE-LTF) 118 and 119 for data , Efficient data payload 120 and packet extension (PE) 121.

在HE WLAN中引入正交頻分多址(Orthogonal Frequency Division Multiple Access,OFDMA)來通過向不同的用戶分派子載波的子集,允許複數個用戶同時進行資料傳輸來增強用戶體驗。在OFDMA中,每一個用戶被分配一組被稱為資源單元(resource unit,RU)的子載波。在HE WLAN中,STA可以在上行OFDMA中傳輸最小尺寸的RU(其大約是2MHz頻寬)。與其20MHz的前導碼相比,其資料部分的功率密度比前導碼部分高9dB。這個窄帶上行OFDMA信號很難被CCA檢測到。因此,STA在特定的窄帶上的子載波上可能比其他子載波要多受9dB的干擾。可以看出,窄帶干擾是HE WLAN中固有的。因此需要處理窄帶干擾的方案。此外,在密集部署的情況下,面對窄帶干擾時的魯棒性對於HE WLAN來說非常重要。增強HE資料部分的每個(PER)性能可以擴展戶外場景的範圍。需要提出新的用於HE資料的調製方式,其可以在比MCS0的SNR更低的SNR下操作。類似地,需要更穩健的用於HE-SIG-B的調製方案。 Orthogonal Frequency Division Multiple Access (OFDMA) is introduced in HE WLAN to enhance the user experience by allocating a subset of subcarriers to different users, allowing multiple users to transmit data at the same time. In OFDMA, each user is assigned a set of subcarriers called a resource unit (RU). In HE WLAN, a STA can transmit the smallest RU (which is approximately 2 MHz bandwidth) in uplink OFDMA. Compared with its preamble of 20MHz, the power density of its data part is 9dB higher than that of the preamble part. This narrow-band uplink OFDMA signal is difficult to detect by CCA. Therefore, the STA may receive 9dB more interference on the subcarriers on a specific narrowband than other subcarriers. It can be seen that narrowband interference is inherent in HE WLAN. Therefore, a solution for narrow-band interference is needed. In addition, in the case of dense deployment, robustness in the face of narrow-band interference is very important for HE WLAN. Enhancing each (PER) performance of the HE data section can extend the range of outdoor scenes. A new modulation scheme for HE data needs to be proposed, which can operate at a lower SNR than the SNR of MCS0. Similarly, a more robust modulation scheme for HE-SIG-B is needed.

因此,在HE WLAN中引入雙子載波調製(dual sub-carrier modulation,DCM)。DCM是處理窄帶干擾的完美解決方案。DCM可以通過在兩個頻域分離的子載波上傳輸同樣的資訊在OFDM系統中引入頻率分集。對於單個用戶的傳輸,DCM方案在一對子載波n和m上調製相同的資訊,即,0<n<NSD/2且m=NSD/2+n,其中NSD是一個資源單元中子載波的總數。對於OFDMA的傳輸,一個頻率資源塊被分配給給定的用戶。對於一個頻率塊的DCM方案與對於單個用戶的OFDM方案相同。可以應用DCM指示方案,這樣對於DCM的編碼和解碼都十分簡單。如第1圖中所示,HE SIG-A 115或HE SIG-B 116包括指示MCS的MCS子欄位和DCM位,該DCM位用於指示DCM是否為該用戶應用到後續的HE SIG-B 116和/或後續的資料有效載荷120,如果DCM被採用且被指示,則相當於傳輸器的AP101使用不同的映射方案在兩個分離的子載波上調製HE PPDU110的相同的編碼位元(bit)。在接收器側,STA102接收HE PPDU 110,對MCS和DCM指示位進行解碼,並相應地執行解調和解碼。 Therefore, dual sub-carrier modulation (DCM) is introduced in HE WLAN. DCM is the perfect solution for narrow-band interference. DCM can introduce frequency diversity in an OFDM system by transmitting the same information on two subcarriers separated in the frequency domain. For the transmission of a single user, the DCM scheme modulates the same information on a pair of subcarriers n and m, that is, 0 <n <NSD / 2 and m = NSD / 2 + n, where NSD is the subcarrier of a resource unit. total. For OFDMA transmission, a frequency resource block is allocated to a given user. The DCM scheme for one frequency block is the same as the OFDM scheme for a single user. A DCM indication scheme can be applied, which makes encoding and decoding of DCM very simple. As shown in Figure 1, HE SIG-A 115 or HE SIG-B 116 includes an MCS subfield indicating the MCS and a DCM bit, which is used to indicate whether the DCM is applied to the subsequent HE SIG-B for the user 116 and / or subsequent data payload 120, if DCM is adopted and indicated, it is equivalent to AP101 of the transmitter using different mapping schemes to modulate the same coding bit of HE PPDU110 on two separate subcarriers (bit ). On the receiver side, the STA 102 receives the HE PPDU 110, decodes the MCS and DCM indicator bits, and performs demodulation and decoding accordingly.

因為通過快速傅裡葉逆變換(Inverse Fast Fourier Transformation,IFFT)操作添加了許多子載波分量,OFDM系統中傳輸信號可以在時域具有高峰值。結果,當與單載波系統相比時,OFDM系統被認為具有較高的峰均功率比(peak-to-average power ratio,PAPR)。當DCM被採用時,雖然其在多徑衰落通道上具有顯著的分集改善,但是其受到高PAPR的影響。根據一個方面,在選擇DCM下的雙子載波的調製和映射方案來降低PAPR。 Because many subcarrier components are added through the Inverse Fast Fourier Transformation (IFFT) operation, the transmission signal in the OFDM system can have high peaks in the time domain. As a result, the OFDM system is considered to have a higher peak-to-average power ratio (PAPR) when compared to a single carrier system. When DCM is adopted, although it has significant diversity improvement on multipath fading channels, it is affected by high PAPR. According to one aspect, the modulation and mapping scheme of the dual subcarriers under DCM is selected to reduce PAPR.

第2圖是根據一方面的無線裝置201和無線裝置211的通信系統200的簡化框圖。對於無線裝置201(例如,傳輸裝置),天線207和208傳輸並接收無線電信號。RF收發模組206,耦接天線207和208,接收來自天線207和208的RF信號,將其轉換為基帶信號並將其發送給處理器203。RF收發模組206也轉換接收到的來自處理器203的基帶信號,將其轉換為RF信號並將其發送到天線207和208。處 理器203處理接收到的基帶信號並調用不同的功能模組和電路來實現無線裝置201的功能。記憶體202存儲程式指令和資料210以控制無線裝置201的操作。 FIG. 2 is a simplified block diagram of a communication system 200 of a wireless device 201 and a wireless device 211 according to an aspect. For the wireless device 201 (for example, a transmission device), the antennas 207 and 208 transmit and receive radio signals. The RF transceiver module 206 is coupled to the antennas 207 and 208, receives RF signals from the antennas 207 and 208, converts them into baseband signals, and sends them to the processor 203. The RF transceiver module 206 also converts the received baseband signal from the processor 203, converts it into an RF signal, and sends it to the antennas 207 and 208. Place The processor 203 processes the received baseband signals and calls different function modules and circuits to implement the functions of the wireless device 201. The memory 202 stores program instructions and data 210 to control the operation of the wireless device 201.

類似地,對於無線裝置211(例如,接收裝置),天線217和218傳輸和接收RF信號。RF收發模組216,耦接天線217和218,接收來自天線217和218的RF信號,將其轉換為基帶信號並將其發送給處理器213。RF收發模組216還轉換接收到的來自處理器213的基帶信號,將其轉換為RF信號並將其發送到天線217和218。處理器213處理接收到的基帶信號並調用不同的功能模組和電路來實現無線裝置211的功能。記憶體212存儲程式指令和資料220以控制無線裝置211的操作。 Similarly, for a wireless device 211 (eg, a receiving device), the antennas 217 and 218 transmit and receive RF signals. The RF transceiver module 216 is coupled to the antennas 217 and 218, receives RF signals from the antennas 217 and 218, converts them into baseband signals, and sends them to the processor 213. The RF transceiver module 216 also converts the received baseband signal from the processor 213, converts it into an RF signal, and sends it to the antennas 217 and 218. The processor 213 processes the received baseband signals and calls different function modules and circuits to implement the functions of the wireless device 211. The memory 212 stores program instructions and data 220 to control the operation of the wireless device 211.

無線裝置201和無線裝置211還包括幾個可以被採用和配置以執行本發明實施例的功能模組和電路。在第2圖所示的示例中,無線裝置201是包括編碼器205、符號映射器/調製器204和OFDMA模組209的傳輸裝置。無線裝置211是包括解碼器215、符號解映射器/解調制器214和OFDMA模組219的接收裝置。需要注意的是,一個無線裝置可以同時是傳輸裝置和接收裝置。不同的功能模組和電路可以通過軟體、固件、硬體及其任意組合來應用和配置。當被處理器203和213執行(例如,通過執行程式指令210和220)時,功能模組和電路允許用於傳輸的無線裝置201和用於接收的無線裝置211執行本發明的實施例。 The wireless device 201 and the wireless device 211 also include several functional modules and circuits that can be adopted and configured to perform embodiments of the present invention. In the example shown in FIG. 2, the wireless device 201 is a transmission device including an encoder 205, a symbol mapper / modulator 204, and an OFDMA module 209. The wireless device 211 is a receiving device including a decoder 215, a symbol demapper / demodulator 214, and an OFDMA module 219. It should be noted that a wireless device can be both a transmitting device and a receiving device. Different functional modules and circuits can be applied and configured through software, firmware, hardware and any combination thereof. When executed by the processors 203 and 213 (for example, by executing program instructions 210 and 220), the functional modules and circuits allow the wireless device 201 for transmission and the wireless device 211 for reception to perform embodiments of the present invention.

在一個示例中,在傳輸器側,無線裝置201生成HE PPDU訊框,並且將MCS和DCM指示位都插入到HE PPDU訊框的信號欄位中。無線裝置201隨後採用對應的MCS和DCM並將HE PPDU發送給接收器。在接收器側,無線裝置211接收該HE PPDU,並且解碼MCS和DCM指示位。如果DCM指示位為0,則接收器基於所指示的MCS來為每個子載波計算接收的位元的對數似然比(logarithm likelihood ratio,LLR)。另一方面,如果DCM指示位為1,則接收器通過執行資源單元的上半頻段的子載波和下半頻段的子載波的LLR的組合來計算LLR。現在將在下文結合附圖描述這種傳輸裝置和接收裝置的各種實施例。 In one example, on the transmitter side, the wireless device 201 generates a HE PPDU frame and inserts both the MCS and DCM indicator bits into the signal field of the HE PPDU frame. The wireless device 201 then adopts the corresponding MCS and DCM and sends the HE PPDU to the receiver. On the receiver side, the wireless device 211 receives the HE PPDU and decodes the MCS and DCM indicator bits. If the DCM indication bit is 0, the receiver calculates a logarithm likelihood ratio (LLR) of the received bit for each subcarrier based on the indicated MCS. On the other hand, if the DCM indicator bit is 1, the receiver calculates the LLR by performing a combination of the LLR of the upper half frequency band subcarrier and the lower half frequency band subcarrier of the resource unit. Various embodiments of such a transmission device and a reception device will now be described below with reference to the drawings.

第3圖是應用雙子載波調製的傳輸裝置300的簡化示意圖。由編碼器/交織器301輸出的RU的編碼和交織的位元被發送給DCM星座(constellation)映射器302(也可以稱為DCM映射器)中。編碼器301可以是LDPC編碼器或BCC編碼器,其中,BCC交織器位於BCC編碼器之前或者之後。DCM星座(constellation)映射器302(也可以稱為DCM映射器)利用可能不同的映射方案在兩個分離的子載波上調製相同的編碼位元。例如,如第3圖中所示,子載波n和子載波m攜帶相同的位元資訊。子載波n是RU的下半頻段中的子載波並且採用映射方案# 1,子載波m是RU的上半頻段中的子載波並且採用映射方案# 2,其中,下半頻段中的子載波比上半頻段中的子載波的頻率低或者比上半頻段中的子載波的頻率高。然後,經調製的信號被映射到RU的資料子載波上,然後發送給IFFT 303並被傳輸。通常,可以預先確定用於DCM的兩個頻率子載波。例如,為了最大化頻率分集,如果n是子載波k,則m是子載波k+(N/2),其中N是用於資料傳輸的一個OFDM符號(symbol)或RU中的子載波的總數。 FIG. 3 is a simplified schematic diagram of a transmission device 300 using dual subcarrier modulation. The encoded and interleaved bits of the RU output by the encoder / interleaver 301 are sent to a DCM constellation mapper 302 (also referred to as a DCM mapper). The encoder 301 may be an LDPC encoder or a BCC encoder, where the BCC interleaver is located before or after the BCC encoder. A DCM constellation mapper 302 (also referred to as a DCM mapper) utilizes a possibly different mapping scheme to modulate the same coding bit on two separate subcarriers. For example, as shown in FIG. 3, subcarrier n and subcarrier m carry the same bit information. Subcarrier n is a subcarrier in the lower half of the RU and adopts the mapping scheme # 1, and subcarrier m is a subcarrier in the upper half of the RU and adopts the mapping scheme # 2, where the subcarrier ratio in the lower half of the RU The frequency of the subcarriers in the upper half band is lower or higher than the frequency of the subcarriers in the upper half band. The modulated signal is then mapped onto the data subcarriers of the RU, then sent to the IFFT 303 and transmitted. In general, two frequency subcarriers for DCM can be predetermined. For example, to maximize frequency diversity, if n is subcarrier k, then m is subcarrier k + (N / 2), where N is the total number of subcarriers in one OFDM symbol or RU for data transmission.

第4圖是用於具有降低峰均功率比(peak-to-average power ratio,PAPR)的DCM的BPSK(binary phase shift keying,二進位相移鍵控)調製映射方案的示例。假設子載波n和子載波m的調製信號分別用s n s m 表示。對於具有DCM的BPSK,可以通過在兩個相同或不同的BPSK星座上映射1比特的編碼位元b 0來獲得s n s m 。根據一個方面,調製的符號s n s m 可以通過分別使用BPSK映射方案# 1和BPSK映射方案# 2映射1比特的編碼位元b0來獲得。選擇BPSK方案# 1和BPSK方案# 2以使得s m =±(s n )。例如,BPSK DCM映射方案可以是:s n =1-2b 0 (1) FIG. 4 is an example of a BPSK (binary phase shift keying) modulation mapping scheme for a DCM having a reduced peak-to-average power ratio (PAPR). Suppose sub-carrier n and m subcarrier modulation signals are represented by s n and s m. For BPSK with DCM and to be encoded by mapping bits 1 bit b 0 on the same or different two BPSK constellation to obtain and s n s m. According to one aspect, the modulation symbols s n s m and 1-bit encoding can be mapped bits b0 are obtained by using the mapping scheme BPSK BPSK mapping scheme # 1 and # 2. Selection scheme BPSK BPSK scheme # 1 and # 2 so that the s m = ± (s n) . For example, the BPSK DCM mapping scheme can be: s n = 1-2 b 0 (1)

s m =(1-2b 0)e jmπ (2) s m = (1-2 b 0 ) e jmπ (2)

在第4圖所示的示例中,相同的編碼位元流被DCM星座映射器調製並且被分別映射到資源單元RU 400的下半頻段的子載波和上半頻段的子載波上, 其中,上半頻段的子載波的頻率比下半頻段的子載波的頻率高或者比下半頻段的子載波的頻率低。使NSD為一個資源單位(RU)中的資料子載波的數量。對於編碼位元流,當使用DCM調製時,則採用DCM星座映射器。例如,編碼位元被調製為複數的前半部分,並被映射到RU的下半頻段的資料子載波[1、2、...、NSD/2]。編碼位元被複製並被調製為複數的後半部分,並映射到RU的上半頻段的資料子載波[NSD/2+1、NSD/2+2、...、NSD]。 In the example shown in FIG. 4, the same coded bit stream is modulated by the DCM constellation mapper and mapped to the lower half-band subcarrier and the upper half-band subcarrier of the resource unit RU 400, respectively. The frequency of the subcarriers in the upper half frequency band is higher than the frequency of the subcarriers in the lower half frequency band or lower than the frequency of the subcarriers in the lower half frequency band. Let NSD be the number of data subcarriers in one resource unit (RU). For a coded bit stream, when DCM modulation is used, a DCM constellation mapper is used. For example, the coded bits are modulated into the first half of the complex number and mapped to the data subcarriers [1, 2, ..., NSD / 2] in the lower half of the RU. The coding bits are copied and modulated into the second half of the complex number and mapped to the data subcarriers [NSD / 2 + 1, NSD / 2 + 2, ..., NSD] in the upper half of the RU.

在基於即將到來的IEEE801.11ax標準的下一代WLAN系統中,每一個站點(station,STA)可以使用一個或複數個資源單元(resource unit,RU)來傳輸信號。RU大小可以是26、52、106、242、484或996個子載波(tone),子載波間隔約為78.1kHz。生成的複數將會被映射到RU的頻段的第一個半頻段的資料子載波和第二個半頻段的數據子載波。RU的第一個半頻段包含子載波1到子載波NSD/2,並且RU的第二個半頻段包含子載波NSD/2到子載波NSD,其中NSD是RU大小。 In the next-generation WLAN system based on the upcoming IEEE801.11ax standard, each station (station, STA) can use one or more resource units (RUs) to transmit signals. The RU size can be 26, 52, 106, 242, 484, or 996 subcarriers (tone), and the subcarrier interval is about 78.1kHz. The generated complex number will be mapped to the data subcarriers of the first half band and the data subcarriers of the second half band of the RU band. The first half frequency band of the RU contains subcarriers 1 to NSD / 2, and the second half frequency band of the RU contains subcarriers NSD / 2 to NSD, where NSD is the size of the RU.

根據一個方面,針對BPSK調製方案的所提出的DCM降低了將要傳輸的資料包的PAPR。由等式(1)和(2)可以看出,根據子載波索引m的值,sm是sn乘以+1或-1。如果m是偶數,那麼sm=sn;如果m是奇數,那麼sm=-sn。通過該操作可知,OFDM信號的PAPR明顯降低。通常,信號x(t)的PAPR被定義為:PAPR=max[x(t)*conj(x(t))]/E[x(t)*conj(x(t))] According to one aspect, the proposed DCM for a BPSK modulation scheme reduces the PAPR of a data packet to be transmitted. As can be seen from equations (1) and (2), according to the value of the subcarrier index m, sm is sn times +1 or -1. If m is even, then sm = sn; if m is odd, then sm = -sn. It can be known through this operation that the PAPR of the OFDM signal is significantly reduced. Generally, the PAPR of the signal x (t) is defined as: PAPR = max [x (t) * conj (x (t))] / E [x (t) * conj (x (t))]

在一個示例中,為了計算資料包的PAPR,執行以下步驟:1)生成長度為4K位元組的隨機二進位資料;2)使用IEEE 802.11ax發射器調製資料以產生複數樣本(complex sample)的時間序列。時間樣本以20MHz採樣;3)PAPR是最大採樣功率除以平均功率的比率。如果複數序列是T並且長度為N,則:Pt=T*conj(T)-每個樣本的功率 In one example, in order to calculate the PAPR of a data packet, the following steps are performed: 1) generating random binary data with a length of 4K bytes; 2) using an IEEE 802.11ax transmitter to modulate the data to generate a complex sample sequentially. Time samples are sampled at 20 MHz; 3) PAPR is the ratio of the maximum sampled power divided by the average power. If the complex sequence is T and the length is N, then: Pt = T * conj (T)-the power of each sample

avgPt=sum(Pt)/N-平均功率 avgPt = sum (Pt) / N-average power

maxPt=max(Pt)-最大功率 maxPt = max (Pt)-maximum power

PAPR=maxPt/avgPt PAPR = maxPt / avgPt

PAPR(dB)=10*log10(maxPt/avgPt) PAPR (dB) = 10 * log10 (maxPt / avgPt)

第5圖是對應於不同的BPSK調製方案的PAPR的累積分佈函數(cumulative distribution function,CDF))的示例。由於每個資料包的PAPR都是不一樣的,因此在第5圖所示的示例中,計算10,000個數據包的PAPR,繪製對應於不同調製方案的PAPR的CDF。使用三種不同的調製方案。在第一調製方案中,使用非DCM BPSK;在第二調製方案中,用不具有特定映射的DCM BPSK;在第三調製方案中,使用具有所提出的特定映射的DCM BPSK。 FIG. 5 is an example of a cumulative distribution function (CDF) of PAPR corresponding to different BPSK modulation schemes. Since the PAPR of each data packet is different, in the example shown in Figure 5, the PAPR of 10,000 packets is calculated, and the CDF corresponding to the PAPR of different modulation schemes is plotted. Three different modulation schemes are used. In the first modulation scheme, non-DCM BPSK is used; in the second modulation scheme, DCM BPSK without specific mapping is used; in the third modulation scheme, DCM BPSK with the proposed specific mapping is used.

對於非DCM BPSK調製,如實曲線所示,平均PAPR約為7.25dB。對於DCM BPSK調製,資料在沒有使用特殊映射的條件下被複製和調製,例如,對於位於下半頻段的子載波和位於上半頻段的子載波採用同樣的BPSK映射。如虛點劃線所示的,平均PAPR約為8.5dB,其高於非DCM BPSK調製。對於具有所提出的特定映射的DCM BPSK,採用第一BPSK映射方案# 1對下半頻段中的子載波調製資料,然後用第二BPSK映射方案# 2對上半頻段的子載波調製複製的資料。如虛曲線所示,平均PAPR非常接近於非DCM BPSK調製方案的PAPR。 For non-DCM BPSK modulation, as shown by the solid curve, the average PAPR is approximately 7.25dB. For DCM BPSK modulation, the data is copied and modulated without using special mapping. For example, the same BPSK mapping is used for subcarriers located in the lower half of the frequency band and subcarriers located in the upper half of the frequency band. As shown by the dashed dotted line, the average PAPR is about 8.5dB, which is higher than the non-DCM BPSK modulation. For the DCM BPSK with the proposed specific mapping, the first BPSK mapping scheme # 1 is used to modulate the subcarriers in the lower half of the band, and then the second BPSK mapping scheme # 2 is used to modulate the subcarriers in the upper half of the band. . As shown by the dashed curve, the average PAPR is very close to that of the non-DCM BPSK modulation scheme.

第6圖是應用DCM解調和解映射的接收裝置600的簡化示意圖。在接收器處,通過FFT 601的接收信號可以寫為:r n =h n s n +v n ---上半頻段的子載波 FIG. 6 is a simplified schematic diagram of a receiving apparatus 600 using DCM demodulation and demapping. At the receiver, the received signal through FFT 601 can be written as: r n = h n s n + v n --- the subcarrier in the upper half

r m =h m s m +v m ---下半頻段的子載波 r m = h m s m + v m --- subcarrier in the lower half

其中- h n h m 是子載波n和m的通道回應矩陣 Where- h n and h m are channel response matrices for subcarriers n and m

- v n v m 被模擬為AWGN(加性高斯白色雜訊,Additive White Gaussian Noise)雜訊 -v n and v m are simulated as AWGN (Additive White Gaussian Noise) noise

如果上半頻段的子載波和下半頻段的子載波的SNR被認為是“好的”,則接收器的解映射器/解調器602可以通過結合來自上半頻段的子載波和下半頻段的子載波的接收信號計算接收的位元的對數似然比(logarithm likelihood ratio,LLR)。可選的,如果下半頻段的子載波的SNR被認為是“不好的”接收器可以選擇計算來自上半頻段的子載波的接收信號計算接收的位元的LLR,如果上半頻段的子載波的SNR被認為是“不好的”接收器可以選擇計算來自下半頻段的子載波的接收信號計算接收的位元的LLR。解調信號隨後被發送到解碼器603以輸出解碼信號。 If the SNRs of the upper and lower half-band subcarriers are considered to be "good", the receiver's demapper / demodulator 602 can combine the subcarriers from the upper and lower half bands by combining A logarithm likelihood ratio (LLR) of the received bits is calculated for the received signals of the subcarriers of. Optionally, if the SNR of the sub-band in the lower half of the band is considered to be "bad", the receiver may choose to calculate the received bit LLR of the received signal from the sub-carrier in the upper half of the band. The SNR of the carrier is considered to be "bad". The receiver may choose to calculate the LLR of the received bits by calculating the received signal from the subcarriers in the lower half of the frequency band. The demodulated signal is then sent to the decoder 603 to output a decoded signal.

第7圖是根據一方面的傳輸並且編碼具有DCM和降低的PAPR HE的PPDU訊框的方法的流程圖。在步驟701中,無線的源站點對資料資訊進行編碼,以將其在正交頻分複用(orthogonal frequency division multiplexing,OFDM)無線局域網中通過資源單元(resource unit,RU)由無線的源站點傳輸至目的站點。在步驟702中,源站點使用第一二進位相移鍵控(binary phase shift keying,BPSK)調製方案將編碼位元調製為第一組調製符號,其中第一組調製符號被映射到RU的第一個半頻段的頻率子載波,其中,第一個半頻段可以是RU的上半頻段或者RU的下半頻段中的一個。在步驟703中,如果應用雙子載波調製(dual carrier modulation,DCM),則源站點使用第二BPSK調製方案將同樣的編碼位元調製為第二組調製符號,其中第二組調製符號被映射到RU的第二個半頻段的頻率子載波,其中,第二個半頻段可以是RU的上半頻段或者RU的下半頻段中的另一個。在步驟704中,源站點將包含調製符號的資料包傳輸給目的站點。在一個示例中,第一組調製符號由sn表示,第二組調製符號由sm表示,其中n和m是子載波索引,並且sm=sn*ej*(pi)*m。 7 is a flowchart of a method of transmitting and encoding a PPDU frame with DCM and reduced PAPR HE according to one aspect. In step 701, the wireless source site encodes the data information, so that it is transmitted from the wireless source through a resource unit (RU) in an orthogonal frequency division multiplexing (OFDM) wireless local area network. The site is transferred to the destination site. In step 702, the source site uses a first binary phase shift keying (BPSK) modulation scheme to modulate the coding bits into a first group of modulation symbols, where the first group of modulation symbols is mapped to the RU. The frequency subcarrier of the first half-band, where the first half-band may be one of the upper half-band of the RU or the lower half-band of the RU. In step 703, if dual carrier modulation (DCM) is applied, the source station uses the second BPSK modulation scheme to modulate the same coding bits into a second group of modulation symbols, where the second group of modulation symbols is A frequency subcarrier mapped to a second half-band of the RU, where the second half-band may be another of the upper half-band of the RU or the lower half-band of the RU. In step 704, the source station transmits the data packet containing the modulation symbol to the destination station. In one example, the first group of modulation symbols is represented by sn, and the second group of modulation symbols is represented by sm, where n and m are subcarrier indexes, and sm = sn * ej * (pi) * m.

區別于先前技術,本發明在在HE WLAN中引入DCM,DCM可以在 頻域分離的兩個子載波上發送相同的資訊。用第一BPSK調製方案將資料包中的編碼位元映射到下半頻段的子載波上;用第二BPSK調製方案將資料包中的相同的編碼位元映射到上半段頻率的子載波上,這樣可以解決窄頻帶干擾的問題並擴展戶外場景的範圍。 Different from the prior art, the present invention introduces DCM in HE WLAN. The same information is sent on two subcarriers separated in the frequency domain. The first BPSK modulation scheme is used to map the coded bits in the data packet to the subcarriers in the lower half of the frequency band; the second BPSK modulation scheme is used to map the same coded bits in the data packet to the first half frequency subcarriers This can solve the problem of narrow-band interference and expand the range of outdoor scenes.

儘管為了教導的目的,結合某些特定實施例描述本發明,但是本發明不限於此。因此,可以執行對所描述的實施例的各種特徵的各種修改,改編及其組合,而不脫離如專利申請範圍中闡述的本發明的範圍。 Although the invention is described in connection with certain specific embodiments for teaching purposes, the invention is not limited thereto. Accordingly, various modifications, adaptations, and combinations of the various features of the described embodiments can be performed without departing from the scope of the invention as set forth in the scope of the patent application.

以上所述僅為本發明之較佳實施例,凡依本發明申請專利範圍所做之均等變化與修飾,皆應屬本發明之涵蓋範圍。 The above description is only a preferred embodiment of the present invention, and all equivalent changes and modifications made in accordance with the scope of patent application of the present invention shall fall within the scope of the present invention.

Claims (10)

一種雙子載波調製方法,包括:對正交頻分複用無線局域網中將由源站點通過資源單元發送到目的站點的資料資訊進行編碼;使用第一二進位相移鍵控調製方案將編碼的位元調製為第一組調製符號,其中所述第一組調製符號被映射到所述資源單元的第一部分的子載波上;如果採用雙子載波調製,則使用第二二進位相移鍵控調製方案將同樣的所述編碼的位元調製為第二組調製符號,其中所述第二組調製符號被映射到所述資源單元的第二部分的子載波上;將包含所述第一組調製符號和/或所述第二組調製符號的資料包傳輸給所述目的站點;其中,所述資源單元的第一部分是所述資源單元的第一半頻段;所述資源單元的第二部分是所述資源單元的第二半頻段,其中,所述資源單元的第一半頻段是所述資源單元的上半頻段和所述資源單元的下半頻段中的其中一個;所述資源單元的第二半頻段是所述資源單元的上半頻段和所述資源單元的下半頻段中的另一個。A dual subcarrier modulation method includes: encoding data information to be transmitted from a source site to a destination site through a resource unit in an orthogonal frequency division multiplexing wireless local area network; and encoding using a first binary phase shift keying modulation scheme The bit modulation of is the first set of modulation symbols, where the first set of modulation symbols is mapped onto the subcarriers of the first part of the resource unit; if dual subcarrier modulation is used, a second binary phase shift key is used The controlled modulation scheme modulates the same coded bits into a second group of modulation symbols, where the second group of modulation symbols is mapped onto a subcarrier of a second part of the resource unit; A data packet of a group of modulation symbols and / or the second group of modulation symbols is transmitted to the destination site; wherein the first part of the resource unit is a first half-band of the resource unit; The second part is the second half frequency band of the resource unit, wherein the first half frequency band of the resource unit is one of the upper half frequency band of the resource unit and the lower half frequency band of the resource unit. One; the second half of the resource unit is the other of the upper half of the resource unit and the lower half of the resource unit. 如申請專利範圍第1項所述的雙子載波調製方法,其中,所述第二組調製符號等於所述第一組調製符號乘以+1或者-1。The dual subcarrier modulation method according to item 1 of the scope of patent application, wherein the second group of modulation symbols is equal to the first group of modulation symbols multiplied by +1 or -1. 如申請專利範圍第1項所述的雙子載波調製方法,其中,第一組調製符號是用於子載波n的sn,所述第二組調製符號是用於子載波m的sm,其中sm=sn*ej*(pi)*m,n和m為子載波索引。The dual subcarrier modulation method according to item 1 of the scope of patent application, wherein the first group of modulation symbols is sn for subcarrier n , and the second group of modulation symbols is sm for subcarrier m , Where s m = s n * e j * (pi) * m , and n and m are subcarrier indexes. 如申請專利範圍第1項所述的雙子載波調製方法,其中,選擇所述第一二進位相移鍵控調製方案和所述第二二進位相移鍵控調製方案以達到第一峰均功率比。The dual subcarrier modulation method according to item 1 of the patent application scope, wherein the first binary phase shift keying modulation scheme and the second binary phase shift keying modulation scheme are selected to achieve a first peak average Power ratio. 如申請專利範圍第4項所述的雙子載波調製方法,其中,如果採用非雙子載波調製則獲得第二峰均功率比,且所述第二峰均功率比實質上與所述第一峰均功率比相同;或者,如果所述第一二進位相移鍵控調製方案和所述第二二進位相移鍵控調製方案相同,則獲得第二峰均功率比,且所述第二峰均功率比比所述第一峰均功率比高。The dual subcarrier modulation method according to item 4 of the scope of patent application, wherein if a non-dual subcarrier modulation is used, a second peak-to-average power ratio is obtained, and the second peak-to-average power ratio is substantially the same as the first The peak-to-average power ratio is the same; or, if the first binary phase-shift keying modulation scheme and the second binary phase-shift keying modulation scheme are the same, a second peak-to-average power ratio is obtained, and the second The peak-to-average power ratio is higher than the first peak-to-average power ratio. 如申請專利範圍第3項所述的雙子載波調製方法,其中,所述n與m之差為N/2,其中,N為所述資源單元中的子載波的總數。The dual subcarrier modulation method according to item 3 of the scope of patent application, wherein the difference between n and m is N / 2, and N is the total number of subcarriers in the resource unit. 一種無線站點,其特徵在於,包括:編碼器,對正交頻分複用無線局域網中將由源站點通過資源單元發送到目的站點的資料資訊進行編碼;調製器,使用第一二進位相移鍵控調製方案將編碼的位元調製為第一組調製符號,其中所述第一組調製符號被映射到所述資源單元的第一部分的子載波上;如果採用雙載波調製,則所述調製器使用第二二進位相移鍵控調製方案將同樣的所述編碼的位元調製為第二組調製符號,其中所述第二組調製符號被映射到所述資源單元的第二部分的子載波上;以及傳輸器,將包含所述第一組調製符號和/或所述第二組調製符號的資料包傳輸給所述目的站點;其中,所述資源單元的第一部分是所述資源單元的第一半頻段;所述資源單元的第二部分是所述資源單元的第二半頻段,其中,所述資源單元的第一半頻段是所述資源單元的上半頻段和所述資源單元的下半頻段中的其中一個;所述資源單元的第二半頻段是所述資源單元的上半頻段和所述資源單元的下半頻段中的另一個。A wireless station is characterized in that it includes: an encoder that encodes information on an orthogonal frequency division multiplexed wireless local area network that will be sent by a source site to a destination site through a resource unit; a modulator that uses a first binary The phase shift keying modulation scheme modulates the coded bits into a first group of modulation symbols, where the first group of modulation symbols is mapped onto the subcarriers of the first part of the resource unit; if dual carrier modulation is used, then The modulator uses a second binary phase shift keying modulation scheme to modulate the same coded bits into a second set of modulation symbols, wherein the second set of modulation symbols is mapped to a second part of the resource unit And a transmitter, transmitting a data packet containing the first group of modulation symbols and / or the second group of modulation symbols to the destination site; wherein the first part of the resource unit is The first half-band of the resource unit; the second part of the resource unit is the second half-band of the resource unit, wherein the first half-band of the resource unit is the One of the upper half frequency band and the lower half frequency band of the resource unit; the second half frequency band of the resource unit is the other of the upper half frequency band of the resource unit and the lower half frequency band of the resource unit. 如申請專利範圍第7項所述的無線站點,其中,所述第二組調製符號等於所述第一組調製符號乘以+1或者-1。The wireless station according to item 7 of the scope of patent application, wherein the second group of modulation symbols is equal to the first group of modulation symbols multiplied by +1 or -1. 如申請專利範圍第7項所述的無線站點,其中,對於子載波n,第一組調製符號為sn,對於子載波m,所述第二組調製符號為sm,其中sm=sn*ej*(pi)*m,n和m為子載波索引。As defined in claim item 7 range wireless station, wherein the sub-carrier n, the first set of modulation symbols S n, the sub-carrier m, the second set of modulation symbols S m, where s m = s n * e j * (pi) * m , where n and m are subcarrier indexes. 如申請專利範圍第9項所述的無線站點,其中,所述n與m之差為N/2,其中,N為所述資源單元中的子載波的總數。The wireless station according to item 9 of the scope of patent application, wherein the difference between n and m is N / 2, and N is the total number of subcarriers in the resource unit.
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