Patent ID: 9537576
Date: 2017-01-03
CPC Classifications: G01S,H03M,H04B,H04L

Claim:
1. A method for encoding a modified IRIG-B time code for high-precision time transfer, comprising generating modified IRIG-B time code frames in an encoding device, each of the frames comprising N number of code elements, N denoting an integer larger than 100, at a code element rate of N bits per second, having fields of a standard TRIG-B time code, a time interval field, a user-defined or padded field, and an ending code element; defining, by the encoding device, three code element values for the frames, wherein the three code element values have pulse width encoding and include a ‘0’ code element at duration of 20% of an index count, a ‘1’ code element at duration of 50% of the index count, and a ‘P’ code element at duration of 80% of the index count; preserving definitions of the first 99 code elements and the last code element in the standard IRIG-B time pulse width encoding rule in each of the frames, and then compressing width of the code elements of the standard IRIG-B by the encoding device; adding message fields between the 100th code element and (N−1)th code element by the encoding device, the added message fields including: transmitting the modified IRIG-B time code frames from the encoding device via space channels, electric cables, or optical fiber.