US-12627422-B2 - Techniques for multiplexing for unique word waveforms in wireless communications

Abstract

Aspects described herein relate to multiplexing, in frequency and to generate a multiplexed set of data subcarriers, a first set of data subcarriers for a first user or a first channel with a second set of data subcarriers for a second user or a second channel, adding at least one set of redundant subcarriers to the multiplexed set of data subcarriers to be transmitted in a unique-word orthogonal frequency division multiplexing (UW-OFDM) waveform to produce at least one of head samples or tail samples for the UW-OFDM waveform, mapping the multiplexed set of data subcarriers and the at least one set of redundant subcarriers as input to an inverse fast Fourier transform (IFFT), and generating the UW-OFDM waveform based on an output of the IFFT.

Inventors

• Iyab Issam SAKHNINI
• Hemant SAGGAR
• Tao Luo
• Junyi Li
• Xiaoxia Zhang
• Peter Gaal

Assignees

• QUALCOMM INCORPORATED

Dates

Publication Date

20260512

Application Date

20220516

Claims (20)

1. 1 . An apparatus for wireless communication, comprising: a transceiver; a memory configured to store instructions; and one or more processors communicatively coupled with the memory and the transceiver, wherein the one or more processors are configured to: multiplex, in frequency and to generate a multiplexed set of data subcarriers, a first set of data subcarriers with a second set of data subcarriers, wherein the first set of data subcarriers are for a first user or a first physical layer channel, and wherein the second set of data subcarriers are for a second user different from the first user or a second physical layer channel different from the first physical layer channel; add at least one set of redundant subcarriers to the multiplexed set of data subcarriers to be transmitted in a unique-word orthogonal frequency division multiplexing (UW-OFDM) waveform to produce at least one of head samples or tail samples for the UW-OFDM waveform; map the multiplexed set of data subcarriers and the at least one set of redundant subcarriers as input to an inverse fast Fourier transform (IFFT); and generate the UW-OFDM waveform based on an output of the IFFT.
2. 2 . The apparatus of claim 1 , wherein the one or more processors are further configured to interleave, based on a permutation matrix, the at least one set of redundant subcarriers with the multiplexed set of data subcarriers to generate a permutation of subcarriers, wherein the one or more processors are configured to map the multiplexed set of data subcarriers and the at least one set of redundant subcarriers at least in part by mapping the permutation of subcarriers as input to the IFFT.
3. 3 . The apparatus of claim 2 , wherein the permutation matrix manages transmit power of at least one of the first set of data subcarriers or the second set of data subcarriers.
4. 4 . The apparatus of claim 1 , wherein the at least one set of redundant subcarriers includes a first set of redundant subcarriers that are a function of the first set of data subcarriers and a second set of redundant subcarriers that are a function of the second set of data subcarriers.
5. 5 . The apparatus of claim 4 , wherein the one or more processors are further configured to generate a permutation of subcarriers at least in part by: interleaving, based on a first permutation matrix, the first set of redundant subcarriers with the first set of data subcarriers; and interleaving, based on one of the first permutation matrix or a second permutation matrix that is different from the first permutation matrix, the second set of redundant subcarriers with the second set of data subcarriers, wherein the one or more processors are configured to map the multiplexed set of data subcarriers and the at least one set of redundant subcarriers at least in part by mapping the permutation of subcarriers as input to the IFFT.
6. 6 . The apparatus of claim 5 , wherein the one or more processors are further configured to transmit, to the first user or for the first physical layer channel, an indication of a proportion of the at least one set of redundant subcarriers that include the first set of redundant subcarriers, wherein interleaving the first set of redundant subcarriers results in adding, to the input of the IFFT, the first set of data subcarriers based on the proportion.
7. 7 . The apparatus of claim 4 , wherein the one or more processors are configured to map the multiplexed set of data subcarriers and the at least one set of redundant subcarriers at least in part by: mapping the first set of redundant subcarriers with the first set of data subcarriers using a first subcarrier mapping matrix; and mapping the second set of redundant subcarriers with the second set of data subcarriers using one of the first subcarrier mapping matrix or a second subcarrier mapping matrix that is different from the first subcarrier mapping matrix.
8. 8 . The apparatus of claim 7 , wherein the one or more processors are further configured to transmit, to the first user or for the first physical layer channel, an indication of a proportion of the at least one set of redundant subcarriers that include the first set of redundant subcarriers, wherein mapping the first set of redundant subcarriers results in adding, to the input of the IFFT, the first set of data subcarriers based on the proportion.
9. 9 . The apparatus of claim 1 , wherein the at least one set of redundant subcarriers is a function of the first set of data subcarriers and the second set of data subcarriers.
10. 10 . The apparatus of claim 1 , wherein the at least one set of redundant subcarriers are within an allocation of resources for the first user or the first physical layer channel or the second user or the second physical layer channel.
11. 11 . The apparatus of claim 1 , wherein the at least one set of redundant subcarriers span a larger bandwidth than an allocation of resources for the first user or the first physical layer channel or the second user or the second physical layer channel.
12. 12 . The apparatus of claim 1 , wherein a portion of the at least one set of redundant subcarriers for the first set of data subcarriers are at least partially within an allocation of resources for the second user or the second physical layer channel.
13. 13 . The apparatus of claim 1 , wherein the one or more processors are configured to transmit, to at least the first user, one or more parameters related to the multiplexed set of data subcarriers, wherein the one or more processors are configured to multiplex the first set of data subcarriers and the second set of data subcarriers based on the one or more parameters.
14. 14 . A method for wireless communications, comprising: multiplexing, in frequency and to generate a multiplexed set of data subcarriers, a first set of data subcarriers with a second set of data subcarriers, wherein the first set of data subcarriers are for a first user or a first physical layer channel, and wherein the second set of data subcarriers are for a second user different from the first user or a second physical layer channel different from the second physical layer channel; adding at least one set of redundant subcarriers to the multiplexed set of data subcarriers to be transmitted in a unique-word orthogonal frequency division multiplexing (UW-OFDM) waveform to produce at least one of head samples or tail samples for the UW-OFDM waveform; mapping the multiplexed set of data subcarriers and the at least one set of redundant subcarriers as input to an inverse fast Fourier transform (IFFT); and generating the UW-OFDM waveform based on an output of the IFFT.
15. 15 . The method of claim 14 , further comprising interleaving, based on a permutation matrix, the at least one set of redundant subcarriers with the multiplexed set of data subcarriers to generate a permutation of subcarriers, wherein mapping the multiplexed set of data subcarriers and the at least one set of redundant subcarriers includes mapping the permutation of subcarriers as input to the IFFT.
16. 16 . The method of claim 15 , wherein the permutation matrix manages transmit power of at least one of the first set of data subcarriers or the second set of data subcarriers.
17. 17 . The method of claim 14 , wherein the at least one set of redundant subcarriers includes a first set of redundant subcarriers that are a function of the first set of data subcarriers and a second set of redundant subcarriers that are a function of the second set of data subcarriers.
18. 18 . The method of claim 17 , further comprising generating a permutation of subcarriers at least in part by: interleaving, based on a first permutation matrix, the first set of redundant subcarriers with the first set of data subcarriers; and interleaving, based on one of the first permutation matrix or a second permutation matrix that is different from the first permutation matrix, the second set of redundant subcarriers with the second set of data subcarriers, wherein mapping the multiplexed set of data subcarriers and the at least one set of redundant subcarriers includes mapping the permutation of subcarriers as input to the IFFT.
19. 19 . The method of claim 18 , further comprising transmitting, to the first user or for the first physical layer channel, an indication of a proportion of the at least one set of redundant subcarriers that include the first set of redundant subcarriers, wherein interleaving the first set of redundant subcarriers results in adding, to the input of the IFFT, the first set of data subcarriers based on the proportion.
20. 20 . The method of claim 17 , wherein mapping the multiplexed set of data subcarriers and the at least one set of redundant subcarriers includes: mapping the first set of redundant subcarriers with the first set of data subcarriers using a first subcarrier mapping matrix; and mapping the second set of redundant subcarriers with the second set of data subcarriers using one of the first subcarrier mapping matrix or a second subcarrier mapping matrix that is different from the first subcarrier mapping matrix.

Description

FIELD OF THE DISCLOSURE Aspects of the present disclosure relate generally to wireless communication systems, and more particularly, to techniques for generating waveforms for wireless communications. DESCRIPTION OF RELATED ART Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems, and single-carrier frequency division multiple access (SC-FDMA) systems. These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. For example, a fifth generation (5G) wireless communications technology (which can be referred to as 5G new radio (5G NR)) is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, 5G communications technology can include: enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; ultra-reliable-low latency communications (URLLC) with certain specifications for latency and reliability; and massive machine type communications, which can allow a very large number of connected devices and transmission of a relatively low volume of non-delay-sensitive information. In some wireless communication technologies, such as 5G NR, waveforms generated for wireless communications can include cyclic prefix (CP)-orthogonal frequency division multiplexing (OFDM), single carrier (SC)-OFDM in a frequency division implementation, such as discrete Fourier transform (DFT)-spread (S)-OFDM, or SC-quadrature amplitude modulation (QAM) in time division implementation. In addition, a given waveform can include CP or guard interval (GI) to avoid inter-symbol interference between symbols of the waveform when transmitted or received in wireless communications. SUMMARY The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later. According to an aspect, a method for wireless communication is provided that includes multiplexing, in frequency and to generate a multiplexed set of data subcarriers, a first set of data subcarriers for a first user or a first channel with a second set of data subcarriers for a second user or a second channel, adding at least one set of redundant subcarriers to the multiplexed set of data subcarriers to be transmitted in a unique-word orthogonal frequency division multiplexing (UW-OFDM) waveform to produce at least one of head samples or tail samples for the UW-OFDM waveform, mapping the multiplexed set of data subcarriers and the at least one set of redundant subcarriers as input to an inverse fast Fourier transform (IFFT), and generating the UW-OFDM waveform based on an output of the IFFT. In another aspect, a method for wireless communication is provided that includes receiving a unique-word orthogonal frequency division multiplexing (UW-OFDM) waveform having head samples or tail samples corresponding to at least one set of redundant subcarriers, generating a mapping of subcarriers by performing a fast Fourier transform (FFT) of the UW-OFDM waveform, demapping, from the mapping of subcarriers, the at least one set of redundant subcarriers and a multiplexed set of data subcarriers, and processing a first set of data subcarriers of the multiplexed set of data subcarriers to obtain data transmitted in the UW-OFDM waveform. In a further example, an apparatus for wireless communication is provided that includes a transceiver, a memory configured to store instructions, and one or more processors communicatively coupled with the transceiver and the memory. The one or more processors are configured to execute the instructions to perform the operations of methods described herein. In another aspect, an apparatus for wireless communication is provided that includes means for performing the operations of methods described herein. In yet another aspect, a computer-readable medium is provided including code executable by one or more processors to perform