Huawei Technologies Co., Limited

Samsung Electronics Co., Ltd.

Nuwan Suresh Ferdinand

Ming Jia

Jianglei Ma

Javad Abdoli

Huang Huang

Qianli Ma

Aspects of the present application provide methods and devices for a phase tracking reference (PT-RS) scheme for use by a single carrier Offset QAM (SC-OQAM) transmitter and receiver to estimate, and correct, phase errors that occur over the communication link between the SC-OQAM transmitter and receiver. A transmitter may set the sign (positive or negative) of PT-RS symbols dynamically allowing the transmitter to better utilize IQ interference caused by data symbols and other PT-RS symbols. Another aspect of the present disclosure provides a receiver that can estimate phase error due to phase noise without knowing the sign of PT-RS symbol or the sign of IQ interference. This type of phase error estimation improves the phase noise estimation performance, and thus may improve the overall block error rate (BLER) performance at the receiver.

Methods and apparatus for using a phase tracking reference signal with a single carrier waveform

Aspects of the present application provide methods and devices for a phase tracking reference (PT-RS) scheme for use by a single carrier Offset QAM (SC-OQAM) transmitter and receiver to estimate, and correct, phase errors that occur over the communication link between the SC-OQAM transmitter and receiver. Phase errors can occur due to, for example, phase noise or carrier frequency offset (CFO). A PT-RS that includes PT-RS symbols can be used to track phase error. As a result of SC-OQAM waveform generation, real-valued PT-RS symbols may incur imaginary valued interference and imaginary-valued PT-RS symbols may incur real-valued interference. In order to effectively use the PT-RS to estimate and compensate for the phase noise, the interference must be appropriately considered.

In one embodiment, a method includes accessing a modulated symbol sequence comprising multiple symbols, generating interpolated symbols to be added between any two adjacent symbols based on an unequal phase change method, generating an interpolated symbol sequence based on adding the generated interpolated symbols for any two adjacent symbols into the two adjacent symbols, and transmitting a waveform to a wireless endpoint device, wherein the waveform is generated based on the interpolated symbol sequence.

Systems and methods for utilizing phase continuity for generating waveforms with low peak-to-average power ratio

A reference signaling scheme is provided that is based on the use of a Zadoff Chu sequence with cyclic repetition, optionally code division multiplexing precoding, together with frequency domain spectral shaping (FDSS). A specific pulse shape design for the FDSS part of the reference signal scheme in some embodiments involves the use of a raised cosine pulse raised to the power of β. The new solution for generating reference signals has a Low peak average power ratio that matches the PAPR of SC-OQAM, good channel estimation performance, and the ability to implement CDM in the frequency domain to increase multiplexing gain.

System and method for generating reference signal with low peak average power ratio

A reference signaling scheme is provided that is based on the use of a Zadoff Chu sequence with cyclic repetition, optionally code division multiplexing precoding, together with frequency domain spectral shaping (FDSS). A specific pulse shape design for the FDSS part of the reference signal scheme in some embodiments involves the use of a raised cosine pulse raised to the power of &#x3b2;. The new solution for generating reference signals has a Low peak average power ratio that matches the PAPR of SC-OQAM, good channel estimation performance, and the ability to implement CDM in the frequency domain to increase multiplexing gain.

A system and method are provided for processing symbols for transmission. The method involves producing a single carrier offset quadrature amplitude modulation (OQAM) waveform signal from a set of K complex symbols. The method further involves pulse shaping 2K frequency domain samples of the OQAM waveform signal with J non-zero coefficients, where the J non-zero coefficients represent a frequency response of a conjugate symmetrical pulse shape, and K&#x2264;J&#x2264;2K&#x2212;1. The approach has the advantage of avoiding self-interference, with the result that better BLER performance may be possible. The approach is applicable to any modulation order and also avoids bandwidth expansion. Flexibility is provided through a trade-off between PAPR vs. spectrum efficiency.

System and method for transmitting and receiving single-carrier OQAM symbols

Aspects of the present application provide methods and devices for time domain implementation of a single carrier waveform such as single carrier quadrature amplitude modulation (QAM) DFT-s-OFDM and single carrier Offset QAM (OQAM). A time domain implementation allows flexible symbol lengths, lower implementation complexity as a large IDFT operation is not required in the time domain and support for variable cyclic prefix (CP) length. An OQAM implementation utilizes a pre-processing step to convert a K complex QAM symbol sequence into a 2K OQAM symbol sequence and generates a sequence for transmission in the time domain as opposed to the frequency domain.

Methods and apparatus for communicating a single carrier waveform

A system and method are provided for processing symbols for transmission. A set of 2K outputs is produced that includes K real components and K imaginary components from K complex symbols. A Fourier transform operation on the 2K outputs produces 2K Fourier transform outputs. Transmit pulse shaping is applied to the 2K Fourier transform outputs. The transmit pulse shape may be Nyquist or non-Nyquist. An inverse Fourier transform operation on the J pulse shaped outputs produces an inverse Fourier transform output. In the receiver, equalization is performed to remove the effect of both the channel and the transmit pulse shape. Nyquist pulse shaping is performed by applying a Nyquist pulse shape prior to converting back to time domain. The approach avoids self-interference, even in situations where the transmit pulse shape is non-Nyquist. The transmitter is free to select a pulse shape to optimize PAPR without being concerned with interference.

System and method for transmitting and receiving single-carrier OQAM symbols with non-nyquist transmit pulse shaping

A system and method are provided for processing symbols for transmission. The method involves producing a set of 2K outputs that include K real components and K imaginary components from K complex symbols, performing a Fourier transform operation on the 2K outputs to produce 2K Fourier transform outputs, pulse shaping the 2K Fourier transform outputs by multiplying each of J of the 2K Fourier transform outputs with a respective one of J non-zero coefficients, where J is odd, and K&#x2264;J&#x2264;2K&#x2212;1, performing an inverse Fourier transform operation on the J pulse shaped outputs to produce an inverse Fourier transform output; and outputting the inverse Fourier transform output. The approach has the advantage of avoiding self-interference, with the result that better BLER performance may be possible. The approach is applicable to any modulation order without bandwidth expansion. Flexibility is provided through a trade-off between PAPR vs. spectrum efficiency.

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Nuwan Suresh Ferdinand