A method and system for time synchronization in a mobile device are disclosed. The method includes negotiating a synchronization schedule. The synchronization schedule defines a plurality of synchronization times for receiving synchronization messages. The method further includes transitioning the mobile device from a first state to a second state to receive a synchronization message. The mobile device uses less power in the first state than the second state and the mobile device cannot receive the synchronization message when in the first state. The method further includes synchronizing a clock component in response to receiving the synchronization message.

A method and a system for synchronizing time information in an ad-hoc network are disclosed. According to the present invention, provided is a method for synchronizing time information in an ad-hoc network as a method by which a plurality of nodes included in an ad-hoc network synchronize a time, the method comprising the steps of: transmitting, by a first node, time information obtained by correcting an initial time using a first self-correcting value at an nth beacon interval, wherein the first self-correcting value is a self-correcting value or a local averaging value at an (n1)th beacon interval; and correcting, by a second node which has received the time information from the first node at the nth beacon interval, time information by calculating a second self-correcting value and a local average value, wherein the first self-correcting value is either the self-correcting value or the local averaging value calculated at the (n1)th beacon interval, and the local averaging value of the second node is an averaging value of time information of one or more neighboring nodes of the second node.

A system and method to improve the accuracy of the measurement of round trip delay in a high accuracy distance measurement (HADM) is disclosed. In one embodiment, the traditional parabolic estimation is used. However, an estimation error is used to compensate for the inaccuracy of the parabolic estimation. This correction may reduce the standard deviation of a measurement by 50% or more. In another embodiment, the parabolic estimation is not used; rather, a different estimation is used, such as an absolute value estimation. In some tests, the absolute value estimation improved the mean measurement value and reduced the standard deviation by 50%.

In retrodirective wireless power delivery environments wireless power receivers generate and send beacon signals that are received by multiple antennas of a wireless power transmission system. The beacon signals provide the charger with timing information for wireless power transfers and also indicate directionality of the incoming signal. As discussed herein, the directionality information is employed when transmitting in order to focus energy (e.g., power wave delivery) on individual wireless power receiver clients. Techniques are described herein for reducing the burden of sampling the beacon signals across the multiple antennas and determining the directionality of the incoming wave. In some embodiments, the techniques leverage previously calculated values to simplify the receiver sampling.

Techniques for automated clock synchronization and control are discussed herein. For example, the techniques can include monitoring of transmissions for known events and identifying timing or frequencies of such events. Deviations in the timing or frequencies of the events from expected times or frequencies may indicate that wireless power transmission system and receiver clocks are not synchronized. The deviations can be used to synchronize the clock for optimum wireless power transfer. Techniques are also described for enhancing clock control mechanisms to provide additional means for managing the adjustments of the clocks, as well as for enabling wireless power transmission systems to mimic client clock offsets for effective synchronization of events (e.g., beacon signals).

A base station can cause a multitude of user devices in a network to be synchronized with the base station's clock using an ultra-lean low-complexity procedure in 5G or 6G. On a predetermined interval, the base station can transmit a timing signal in the guard-space of a predetermined resource element. The timing signal is a 180-degree phase reversal of the cyclic prefix centered in the guard-space. Each user device can receive the timing signal, determine how far the received timestamp point is from the middle of the guard-space (as viewed by the user device), and thereby determine a timing error between the user device clock and the base station clock, and correct the user device clock accordingly. In addition, the user device can average the timing adjustments over a number of instances, thereby determining a frequency offset if the average differs significantly from zero, and thereby adjust the clock frequency.

This application discloses example signal sending methods and apparatuses, and example signal processing methods and apparatuses. One example method includes generating, by a terminal device, a channel sounding reference signal (SRS). The terminal device can then send the SRS to a target base station, where the target base station detects, by using the SRS, that a change range of an uplink timing location of the terminal device is not less than a length of one SRS symbol.

The present disclosure provides methods, systems, and devices for correcting clock skew between devices for accurate estimation of one-way delays. A first computing device can transmit, to a second computing device, a plurality of time synchronization requests. The first computing device can receive, from the second computing device, a time synchronization response for each time synchronization request. The first computing device can calculate, for each time synchronization request, a round trip time for the time synchronization request. The first computing device can determine an estimated clock skew based, at least in part, on a minimum round-trip time from a plurality of calculated round trip times. The first computing device can estimate a one-way communication delay between the first computing device and the second computing device based, at least in part, on the time synchronization request, the time synchronization response, and the estimated clock skew.

A system for synchronizing communications in a radio ranging process involves transmitting calibration signals according to a predetermined schedule of nominal transmission times. Timing offsets are determined. A start time is determined for a transmission of a ranging signal. The start time is earlier than a nominal start time of the ranging signal by at least the largest timing offset. Another system for synchronization involves a radio device transmitting a calibration signal to a second radio device and receiving a calibration response signal from the second radio device. A time-of-flight value is determined in dependence on a time of departure of the calibration signal and a time of arrival of the calibration response signal. A ranging signal is transmitted at a time determined in dependence on the determined time-of-flight value. A ranging response signal is received and processed to determine a range value.