Time synchronization for wireless device

A first wireless device comprising:

• an antenna configured to receive a modulated signal from a second wireless device, the modulated signal indicating information of a first pulse per second (PPS) signal for time synchronization, and the first PPS signal being received by the second wireless device via a network protocol for time synchronization or a Global Navigation Satellite System (GNSS) receiver;
• a directional coupler connected to the antenna and configured to assign the received modulated signal;
• a demodulator connected to the directional coupler and configured to demodulate the received modulated signal into a second PPS signal, wherein the demodulator comprises:
• a filter connected to the directional coupler and configured to obtain a filtered signal indicating the information of the first PPS signal by filtering a Wi-Fi signal from the received modulated signal;
• and
• a demodulation module connected to the filter and configured to generating the second PPS signal based on the filtered signal;
• a delay control unit connected to the demodulator and configured to
• determine a delay offset between the first PPS signal and the second PPS signal;
• and
• recover the first PPS signal for time synchronization based on the second PPS signal and the delay offset.

A second wireless device comprising:

• a signal generation module configured to generate a sine wave signal;
• a power amplifier connected to the signal generation module and configured to amplify a power of the sine wave signal;
• a radio frequency (RF) switch connected to the power amplifier and configured to:
• receive a first pulse per second (PPS) signal for time synchronization via a network protocol for time synchronization or a Global Navigation Satellite System (GNSS) receiver, and
• generate a modulated signal based on the received first PPS signal and the sine wave signal;
• a directional coupler connected to the RF switch and configured to couple the modulated signal with a Wi-Fi signal;
• an antenna connected to the directional coupler and configured to transmit the modulated signal to the second wireless device for time synchronization between a first wireless device and the second wireless device.