A method in a node is disclosed. The method comprises receiving a signal, and obtaining a first oversampled received signal by sampling the received signal according to a symbol rate. The method further comprises estimating a first frequency offset based on the first oversampled received signal, the first frequency offset estimated using an estimation range limited to one of a bandwidth of the received signal or the symbol rate of the received signal, and obtaining a second oversampled received signal by sampling the received signal according to N times the symbol rate, wherein N is greater than 1. The method further comprises estimating a true frequency offset based on the first frequency offset estimate and the second oversampled received signal.

A method in a node is disclosed. The method comprises receiving a signal, and obtaining a first oversampled received signal by sampling the received signal according to a symbol rate. The method further comprises estimating a first frequency offset based on the first oversampled received signal, the first frequency offset estimated using an estimation range limited to one of a bandwidth of the received signal or the symbol rate of the received signal, and obtaining a second oversampled received signal by sampling the received signal according to N times the symbol rate, wherein N is greater than 1. The method further comprises estimating a true frequency offset based on the first frequency offset estimate and the second oversampled received signal.

Aspects of frequency error detection with Physical Broadcast CHannel (PBCH) frequency hypothesis are described. For example, a method and apparatus are disclosed for frequency tracking in a user equipment (UE) may include detecting a change in frequency that exceeds a pull-in range of a frequency tracking loop (FTL) of the UE. The method and apparatus may also include identifying a tracking recovery frequency in response to the change in frequency being detected, wherein the tracking recover frequency is identified from a set of frequency hypotheses and based on decoding of the PBCH received by the UE. The method and apparatus may further include updating the FTL with the tracking recovery frequency.

Methods and systems for correcting carrier frequency offsets (CFOs) in a wireless transceiver are disclosed. The method includes receiving a first predetermined number of data packets and analyzing the first predetermined number of data packets to determine one or more wireless link quality metrics. The method includes adjusting a local oscillator in accordance with a first local oscillator adjustment strategy. The method includes receiving a second predetermined number of data packets and analyzing the second predetermined number of data packets to determine the one or more wireless link quality metrics. The method includes repeating the first local oscillator adjustment strategy if the wireless link quality metrics improve. The method includes changing to a second local oscillator adjustment strategy if the wireless link quality metrics worsen and adjusting the local oscillator in accordance with the second local oscillator adjustment strategy.

A communication packet (PHY packet) can include a plurality of subfields with a common symbol sequence that can be used for autocorrelation. The symbol sequence of each subfield may be multiplied by a constant of either +1 or 1, based on a different bit of a maximal length sequence, which can enable cross-correlation. Thus, this packet design enables packet detection, symbol timing recovery, and carrier frequency offset estimation.

According to some embodiments, a method performed by a network node comprises receiving a plurality of radio signal samples; estimating parameters for a first hypothesis function, the first hypothesis function hypothesizing that that the plurality of radio signal samples only contains background noise; estimating parameters for a second hypothesis function, the second hypothesis function hypothesizing that that the plurality of radio signal samples contains background noise plus one or more radio pulses; performing a log-likelihood ratio test for the first hypothesis function and the second hypothesis function; and based on the log-likelihood ratio test, determining whether a radio pulse is present in the plurality of radio signal samples.

A method in a node is disclosed. The method comprises receiving a signal, and obtaining a first oversampled received signal by sampling the received signal according to a symbol rate. The method further comprises estimating a first frequency offset based on the first oversampled received signal, the first frequency offset estimated using an estimation range limited to one of a bandwidth of the received signal or the symbol rate of the received signal, and obtaining a second oversampled received signal by sampling the received signal according to N times the symbol rate, wherein N is greater than 1. The method further comprises estimating a true frequency offset based on the first frequency offset estimate and the second oversampled received signal.

Methods and systems for correcting carrier frequency offsets (CFOs) in a wireless transceiver are disclosed. The method includes receiving a first predetermined number of data packets and analyzing the first predetermined number of data packets to determine one or more wireless link quality metrics. The method includes adjusting a local oscillator in accordance with a first local oscillator adjustment strategy. The method includes receiving a second predetermined number of data packets and analyzing the second predetermined number of data packets to determine the one or more wireless link quality metrics. The method includes repeating the first local oscillator adjustment strategy if the wireless link quality metrics improve. The method includes changing to a second local oscillator adjustment strategy if the wireless link quality metrics worsen and adjusting the local oscillator in accordance with the second local oscillator adjustment strategy.

Described herein are systems and methods for accurately estimating and removing a carrier frequency offset. One exemplary embodiment relates to a system comprising a frequency offset detection circuit detecting a carrier frequency offset in an optical signal, and a frequency testing circuit calculating an estimated frequency offset value of the carrier frequency offset, wherein the frequency testing circuit removes a carrier phase based on the estimated frequency offset value and recovers the optical signal. Another exemplary embodiment relates to a method comprising detecting a carrier frequency offset in an optical signal, calculating an estimated frequency offset value of the carrier frequency offset, removing a carrier phase based on the estimated frequency offset value, and recovering the optical signal.

A method in a node is disclosed. The method comprises receiving a signal, and obtaining a first oversampled received signal by sampling the received signal according to a symbol rate. The method further comprises estimating a first frequency offset based on the first oversampled received signal, the first frequency offset estimated using an estimation range limited to one of a bandwidth of the received signal or the symbol rate of the received signal, and obtaining a second oversampled received signal by sampling the received signal according to N times the symbol rate, wherein N is greater than 1. The method further comprises estimating a true frequency offset based on the first frequency offset estimate and the second oversampled received signal.