Patent ID: 11930463
Assignee: CHINA UNIVERSITY OF MINING AND TECHNOLOGY
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 3:
4. The synchronization method based on the time service and positioning network system for the underground chain-shaped large space in the coal mine according claim 3, wherein S1 includes following steps:
S11, adjusting, based on ground environment, a vibration frequency of a built-in adjustable crystal oscillator of each base station 1 to a same frequency and a same phase as an atomic clock of a ground satellite, for each base station 1 in the time service and positioning network system;
S12, arranging, when a stabilization time of the frequency of the built-in adjustable crystal oscillator of the base station 1 based on the ground environment is greater than a preset time, the base station 1 at a corresponding position in the underground roadway of the target coal mine, for each base station 1, then setting up other base stations in an area segment where the base station 1 is located; transmitting, through the optical fibers, the information table data between the ad-hoc network base stations; completing an arrangement and a communication network of the ad-hoc network base stations, and proceeding step S13 after an arrangement of all of the ad-hoc network base stations in the underground roadway of the target coal mine is completed;
S13, transmitting, by each base station 1 receiving a crystal oscillator adjustment signal sent by the control center, the time reference information to a base station 2 corresponding to each base station 1; adjusting the vibration frequency of the built-in crystal oscillator of base station 2 until an error value for the time reference of the base station 2 is less than the preset error value, thus adjusting the error values for the time references of all of the ad-hoc network base stations in the area segment where the base station 1 is located sequentially, and completing a time synchronization of the time service and positioning network system; and
S14, sending, by each ad-hoc network base station, an adjustment progress to the mining switch; and sending, by the mining switch, the adjustment progress of each ad-hoc network base station to the mining computer or the control center.