Wireless communication method and device

Abstract

The invention discloses a wireless communication method and equipment, and the method comprises the steps: generating a plurality of repeated frequency domain segments, and enabling each repeated frequency domain segment to comprise a plurality of OFDM (Orthogonal Frequency Division Multiplexing) subcarriers; performing a phase rotation operation on the plurality of repeated frequency domain segments, including applying different phase rotations to different OFDM subcarriers within the same repeated frequency domain segment; and generating an OFDM signal according to an output of the phase rotation operation.

Description

[0001] Cross-references

[0002] This application claims priority to U.S. Provisional Application No. 63 / 711,167 (filed October 24, 2024), the contents of which are incorporated herein by reference. Technical Field

[0003] This invention relates to wireless communication, and more specifically, to a method and apparatus for applying different phase rotations to different orthogonal frequency division multiplexing (OFDM) subcarriers within the same repeating frequency domain segment to reduce the peak-to-average power ratio (PAPR). Background Technology

[0004] Wireless local area network (WLAN) technology is one of the most popular wireless communication technologies worldwide. For example, WLAN technology is widely used in consumer electronic devices, including desktop computers, laptops, and smartphones, to achieve convenient and high-speed wireless communication. The IEEE 802.11 standard is a set of WLAN protocols developed by the Institute of Electrical and Electronics Engineers (IEEE). With the development of the IEEE 802.11 standard, OFDM has become a fundamental technology in Wi-Fi systems. OFDM has high spectral efficiency and the ability to resist signal attenuation caused by multipath propagation. However, a significant drawback of OFDM is its high PAPR (Programmable Array Parameters Per Second), which can lead to reduced power amplifier efficiency and increased distortion. A typical PAPR reduction solution is the cropping method, but this method usually introduces a degradation in signal quality. Therefore, there is an urgent need for an innovative PAPR reduction scheme designed to effectively reduce PAPR while avoiding a degradation in signal quality. Summary of the Invention

[0005] One of the objectives of this invention is to provide a method and apparatus for applying different phase rotations to different orthogonal frequency division multiplexing (OFDM) subcarriers within the same repeating frequency domain segment in order to reduce peak-to-average power ratio (PAPR).

[0006] According to a first aspect of the present invention, an exemplary wireless communication method is disclosed. The exemplary wireless communication method includes: generating a plurality of repeating frequency domain segments, wherein each of the plurality of repeating frequency domain segments includes a plurality of orthogonal frequency division multiplexing (OFDM) subcarriers; performing a phase rotation operation on the plurality of repeating frequency domain segments, including: applying different phase rotations to different OFDM subcarriers within the same repeating frequency domain segment; and generating an orthogonal frequency division multiplexing (OFDM) signal based on the output of the phase rotation operation.

[0007] According to a second aspect of the present invention, an exemplary wireless communication device is disclosed. The exemplary wireless communication device includes a first processing circuit, a phase rotation circuit, and a second processing circuit. The first processing circuit is configured to generate a plurality of repeating frequency domain segments, wherein each of the plurality of repeating frequency domain segments includes a plurality of orthogonal frequency division multiplexing (OFDM) subcarriers. The phase rotation circuit is configured to perform a phase rotation operation on the plurality of repeating frequency domain segments, including applying different phase rotations to different OFDM subcarriers within the same repeating frequency domain segment. The second processing circuit is configured to generate an orthogonal frequency division multiplexing (OFDM) signal based on the output of the phase rotation circuit.

[0008] These, and other objectives of the invention, will become apparent to those skilled in the art upon reading the following detailed description and the preferred embodiments shown in the accompanying drawings. Attached Figure Description

[0009] Figure 1 This is a schematic diagram illustrating a wireless communication device that supports the proposed peak-to-average power ratio (PAPR) reduction scheme according to an embodiment of the present invention.

[0010] Figure 2 This is a schematic diagram illustrating an orthogonal frequency division multiplexing (OFDM) transmitter with peak-to-average power ratio (PAPR) reduction capability according to an embodiment of the present invention.

[0011] Figure 3 This is a schematic diagram illustrating linear phase rotation applied to repeating frequency domain segments according to an embodiment of the present invention. Detailed Implementation

[0012] Certain terms are used in the following description and claims to refer to specific components. Those skilled in the art will understand that electronic device manufacturers may use different names to refer to the same component. This document is not intended to distinguish between components with different names but identical functions. In the following description and claims, the terms "comprising" and "including" are used in an open-ended manner and should therefore be interpreted as "including but not limited to...". Furthermore, the term "coupled" means a direct or indirect electrical connection. Thus, if one device is coupled to another device, the connection can be achieved through a direct electrical connection or indirectly through other devices and connections.

[0013] Figure 1 This is a schematic diagram of a wireless communication device supporting the proposed Peak-to-Average Power Ratio (PAPR) reduction scheme according to an embodiment of the present invention. The wireless communication device 100 may be a Wi-Fi device conforming to existing or next-generation Wi-Fi standards, wherein the Wi-Fi device may be an access point (AP) or a non-AP workstation (STA). However, this is for illustrative purposes only and is not intended to limit the invention. In practical applications, any Orthogonal Frequency Division Multiplexing (OFDM) based wireless communication device using the proposed PAPR reduction scheme falls within the scope of this invention.

[0014] like Figure 1 As shown, the wireless communication device 100 may include a processor 102, a memory 104, a control circuit 106, and a wireless interface circuit 108, wherein the wireless interface circuit 108 may include a transmitter (TX) circuit 110 and a receiver (RX) circuit 112. The memory 104 is configured to store program code. The processor 102 is configured to load and execute the program code to manage the wireless communication device 100. The control circuit 106 is configured to control communication with other wireless communication devices. For example, the control circuit 106 controls the TX circuit 110 of the wireless interface circuit 108 to send data packets (e.g., Wi-Fi Physical Layer Protocol Data Units (PPDUs)) to peer devices and controls the RX circuit 112 of the wireless interface circuit 108 to receive data packets (e.g., Wi-Fi PPDUs) from peer devices.

[0015] It is important to note that Figure 1 Only components relevant to this invention are shown. In practical applications, the wireless communication device 100 may include other components to achieve the specified function.

[0016] In this embodiment, the wireless communication device 100 supports the proposed PAPR reduction scheme. Specifically, the wireless interface circuit 108 (particularly the TX circuit 110 of the wireless interface circuit 108) includes a phase rotation circuit 114, which is configured to apply different phase rotations to different OFDM subcarriers within the same repeating frequency domain segment, thereby introducing decorrelation between multiple repeating frequency domain segments of OFDM data packets (e.g., Wi-Fi PPDUs).

[0017] Figure 2 This is a schematic diagram of an OFDM transmitter with PAPR reduction function according to an embodiment of the present invention. The OFDM transmitter 200 may include a first processing circuit 202, a phase rotation circuit 204, and a second processing circuit 206. For example, the OFDM transmitter 200 may be... Figure 1A portion of the TX circuit 110 shown, while Figure 1 The phase rotation circuit 114 shown can be implemented by the phase rotation circuit 204. The first processing circuit 202 is configured to generate multiple repeating frequency domain segments 211_1-211_N ( ), where each repeating frequency domain segment 211_1-211_N includes multiple segments composed of ( and OFDM subcarriers indexed by ) . For example, the first processing circuit 202 may include an encoder circuit 208 and a mapper circuit 210, wherein the encoder circuit 208 can process the input bitstream D IN Channel coding is performed, and the mapper circuit 210 can perform modulation (e.g., phase shift keying (PSK) or quadrature amplitude modulation (QAM)) on the output of the encoder circuit 208 to generate multiple symbols. In this embodiment, the same symbol is carried by each repeating frequency domain segment 211_1-211_N in different subbands / subchannels. In some embodiments of the invention, each repeating frequency domain segment 211_1-211_N carries a portion of the information of the Wi-Fi PPDU. For example, a portion of the Wi-Fi PPDU may be a preamble, including a conventional short training field (L-STF), a conventional signal field (L-SIG), a repeating L-SIG field (RL-SIG), a high throughput signal field (HT-SIG), an ultra-high throughput signal-A field (VHT-SIG-A), an efficient signal-A field (HE-SIG-A), an efficient signal-B field (HE-SIG-B), a universal signal field (U-SIG), an extremely high throughput signal field (EHT-SIG), and / or an ultra-high reliability signal field (UHR-SIG).

[0018] Phase rotation circuit 204 is configured to perform phase rotation operation on repeating frequency domain segments 211_1-211_N. Second processing circuit 206 is configured to generate an OFDM signal S in the time domain based on the output of phase rotation circuit 204. OFDM For example, the second processing circuit 206 may include an inverse fast Fourier transform (IFFT) circuit 214, wherein the OFDM signal S OFDM It is obtained by combining the IFFT output of repeated frequency domain segments 211_1-211_N with the phase rotation of each subcarrier.

[0019] According to the proposed PAPR reduction scheme, the phase rotation operation performed by the phase rotation circuit 204 includes the same repeating frequency domain segment 211_n ( Different phase rotations are applied to different OFDM subcarriers within the same region. For example... Figure 2As shown, the phase rotation circuit 204 may include multiple multipliers 212_1-212_N ( ), where multiplier 212_1 is configured to multiply OFDM subcarriers (by the same repeating frequency domain segment 211_1) within the same frequency domain segment 211_1. (Index) Apply different phase rotations The multiplier 212_N is configured to multiply OFDM subcarriers (by the same repeating frequency domain segment 211_N) within the same frequency domain segment 211_N. (Index) Apply different phase rotations Specifically, repeating frequency domain segments Phase rotation OFDM subcarrier index It is set by the following formula: = ,in Indicates the subcarrier spacing (Hz). Represents repeating frequency domain segments The direction of rotation in Represents repeating frequency domain segments Time delay in rotation direction. The time delay can be set to +1 or -1 depending on the actual design. The value can be set to random based on the actual design.

[0020] In some embodiments of the invention, the phase rotation operation performed by the phase rotation circuit 204 may include applying a linear phase rotation to each repeating frequency domain segment 211_1-211_N. Figure 3 This is a schematic diagram illustrating, according to an embodiment of the present invention, the repeated frequency domain segment 211_n ( Applying linear phase rotation In this embodiment, the rotation direction... It is set to +1. Therefore, when the OFDM subcarrier index... When increasing, phase rotation (Right now, = (Linear increase.) Those skilled in the art should understand that if the direction of rotation... Set to -1 when OFDM subcarrier index When increasing, phase rotation (Right now, = The value will decrease linearly.

[0021] Consider a scenario where the wireless communication device 100 is a Wi-Fi device (e.g., an access point) supporting a 320MHz bandwidth (BW320), which can be divided into 16 20MHz sub-bands / sub-channels. Therefore, the first processing circuit 202 generates 16 repeating frequency domain segments 211_1-211_16 (…). Each subcarrier occupies a different 20MHz sub-band / sub-channel within a 320MHz bandwidth. Subcarrier spacing It can be 312.5 kHz. The rotation direction of the repeating frequency domain segments 211_1-211_16. It can be set to [1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1]. The time delay of the repeating frequency domain segment 211_1-211_16. The parameters can be set to [550ns 175ns 150ns 75ns 400ns 175ns 275ns 525ns 300ns 500ns 150ns 600ns 525ns 125ns 575ns 500ns]. However, these are for illustrative purposes only and do not imply limitation of the invention. In practical applications, the parameters... and It can be set to any value that achieves the minimum peak-to-average power ratio (PAPR). For example, the parameter... and It can be predefined based on experimental or simulation results.

[0022] Compared with traditional time-domain clipping methods for reducing PAPR, the proposed PAPR reduction scheme can achieve effective PAPR reduction without affecting the signal error vector amplitude (EVM) and signal power.

[0023] Those skilled in the art will readily observe that numerous modifications and alterations can be made to the apparatus and method while retaining the edible content of the present invention. Therefore, the above disclosure should be interpreted only within the scope and limits of the dependent claims.

Claims

1. A wireless communication method, comprising: Multiple repeating frequency domain segments are generated, each of which includes multiple orthogonal frequency division multiplexing (OFDM) subcarriers; Perform a phase rotation operation on the multiple repeating frequency domain segments, including: Apply different phase rotations to different OFDM subcarriers within the same repeating frequency domain segment; as well as An OFDM signal is generated based on the output of this phase rotation operation.

2. The wireless communication method of claim 1, wherein the phase rotation operation includes applying linear phase rotation to the plurality of repeating frequency domain segments.

3. The wireless communication method of claim 1, wherein each of the repeating frequency domain segments carries a portion of the information of a Wi-Fi Physical Layer Protocol Data Unit (PPDU).

4. The wireless communication method of claim 3, wherein a portion of the Wi-Fi PPDU includes a preamble.

5. The wireless communication method of claim 1, wherein the phase rotation of the repeated frequency domain segment n The OFDM subcarrier index k is set by the following formula: = ,in Indicates the subcarrier spacing. This indicates the rotation direction within the repeated frequency domain segment n. This represents the time delay in the repeated frequency domain segment n.

6. A wireless communication device, comprising: A first processing circuit is configured to generate a plurality of repeating frequency domain segments, wherein each of the plurality of repeating frequency domain segments includes a plurality of orthogonal frequency division multiplexing (OFDM) subcarriers; A phase rotation circuit configured to perform a phase rotation operation on the plurality of repeating frequency domain segments, including: Apply different phase rotations to different OFDM subcarriers within the same repeating frequency domain segment; as well as The second processing circuit is configured to generate an OFDM signal based on the output of the phase rotation circuit.

7. The wireless communication device of claim 6, wherein the phase rotation operation includes applying linear phase rotation to the plurality of repeating frequency domain segments.

8. The wireless communication device of claim 6, wherein each of the repeating frequency domain segments carries a portion of the information of a Wi-Fi Physical Layer Protocol Data Unit (PPDU).

9. The wireless communication device of claim 8, wherein a portion of the Wi-Fi PPDU includes a preamble.

10. The wireless communication device of claim 6, wherein the phase rotation of the repeating frequency domain segment n The OFDM subcarrier index k is set by the following formula: = ,in Indicates the subcarrier spacing. This indicates the rotation direction within the repeated frequency domain segment n. This represents the time delay in the repeated frequency domain segment n.

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