To provide improved phase noise tolerance and improved identification of certain fault types, a modulation/demodulation procedure is disclosed for 5G and 6G. The transmitter can modulate a message according to the amplitude and phase of the overall waveform to be emitted, modulated according to predetermined amplitude and phase levels of the modulation scheme. The receiver can then separate the received waveform into orthogonal I and Q branches and measure their branch amplitudes, as usual. The receiver can then convert the branch amplitude measurements back into the original amplitude-phase modulation parameters using formulas provided. The receiver can then demodulate the message by comparing the overall amplitude and phase of each message element to the predetermined amplitude and phase levels of the modulation scheme, which thereby provides substantially increased phase noise tolerance at high frequencies. The procedure can also diagnose fault types and identify faulted message elements specifically, among other benefits.

Example operations may include determining a first noise estimate of noise that propagates along a receive path of a device. The operations may further include determining a second noise estimate of the noise and determining a cross-relationship estimate with respect to the noise. In addition, the operations may include adjusting one or more correction filters configured to correct for imbalances between a first branch and a second branch of the receive path. The adjusting may be based on the first noise estimate, the second noise estimate, and the cross-relationship estimate.

Reliable communications is a central goal of 5G and 6G. However, due to signal fading at high frequencies and interference due to crowding, message faults continue to be a problem. Disclosed are methods for base station and user devices to adjust the modulation scheme according to the types of faults received, including amplitude faults (incorrectly demodulated amplitude levels) and phase faults (incorrectly demodulated phase levels), among others. The base station can select a more suitable modulation scheme based on the types of faults observed by user devices, such as modulation schemes with more or fewer amplitude levels and phase levels. In some versions, the number of amplitude levels is different from the number of phase levels, to combat specific fault problems.

A method, an apparatus and a computer program product for enhancing reception of signals in a wireless communication system. A signal containing a frame including a plurality of symbols is received on an uplink communication channel. An angular position of at least one symbol in the plurality of symbols in a constellation of symbols is detected. The plurality of symbols include equalized symbols. An angular difference corresponding a phase error between the detected angular position of the symbol and an expected reference angular position in the constellation of symbols corresponding to an expected reference symbol corresponding to the received frame is determined. Using the determined phase error, a phase of the symbol is compensated.

One embodiment of the present invention provides a method for transmitting, by a receiving terminal, a feedback signal to a transmitting terminal in a wireless communication system, the method comprising the steps of: receiving, by the receiving terminal, a reference signal from the transmitting terminal; and transmitting, by the receiving terminal, the feedback signal for the reference signal to the transmitting terminal, wherein the feedback signal is transmitted on the basis of compensation for a phase change that occurs when the reference signal is received.

A UE determines a respective set of subcarriers from N subcarriers in each OFDM symbol of M1 consecutive OFDM symbols within a slot. The respective set of subcarriers carries a respective set of SRSs that form transmission combs of a transmission comb size. The respective set of subcarriers in one of the M1 consecutive OFDM symbols do not overlap in frequency domain with the respective set of subcarriers in any other one of the M1 consecutive OFDM symbols. The UE applies the respective set of phase rotations to the respective set of SRSs in each OFDM symbol to obtain a cyclic shift. The UE maps the respective set of SRSs applied with phase rotations to the respective set of subcarriers in each OFDM symbol. The UE transmits the respective sets of SRSs in the M OFDM symbols.

A UE determines a respective set of subcarriers from N subcarriers in each OFDM symbol of M1 consecutive OFDM symbols within a slot. The respective set of subcarriers carries a respective set of SRSs that form transmission combs of a transmission comb size. The respective set of subcarriers in one of the M1 consecutive OFDM symbols do not overlap in frequency domain with the respective set of subcarriers in any other one of the M1 consecutive OFDM symbols. The UE applies the respective set of phase rotations to the respective set of SRSs in each OFDM symbol to obtain a cyclic shift. The UE maps the respective set of SRSs applied with phase rotations to the respective set of subcarriers in each OFDM symbol. The UE transmits the respective sets of SRSs in the M OFDM symbols.

Example operations may include determining a first noise estimate of noise that propagates along a receive path of a device. The operations may further include determining a second noise estimate of the noise and determining a cross-relationship estimate with respect to the noise. In addition, the operations may include adjusting one or more correction filters configured to correct for imbalances between a first branch and a second branch of the receive path. The adjusting may be based on the first noise estimate, the second noise estimate, and the cross-relationship estimate.

One embodiment of the present invention provides a method for transmitting, by a receiving terminal, a feedback signal to a transmitting terminal in a wireless communication system, the method comprising the steps of: receiving, by the receiving terminal, a reference signal from the transmitting terminal; and transmitting, by the receiving terminal, the feedback signal for the reference signal to the transmitting terminal, wherein the feedback signal is transmitted on the basis of compensation for a phase change that occurs when the reference signal is received.

A method and apparatus for transmitting PPDU in a wireless LAN system are proposed. Specifically, a transmitter generates the PPDU, and transmits the PPDU to a receiver through a 320 MHz band in which some bands are punctured. The PPDU includes a legacy preamble and an EHT field. The legacy preamble includes L-STF and L-LTF. The legacy preamble is generated by applying a first phase rotation value or a second phase rotation value. The first phase rotation value is obtained on the basis of a third phase rotation value and a fourth phase rotation value. The third phase rotation value is a phase rotation value having repeated a phase rotation value defined for an 80 MHz band in an 802.11ax system. The fourth phase rotation value is a phase rotation value defined in units of the 80 MHz band in the 320 MHZ band on the basis of an optimal PAPR of the L-LTF.