CN100351644C

CN100351644C - Time generating method for single board precise global positioning system

Info

Publication number: CN100351644C
Application number: CNB031153259A
Authority: CN
Inventors: 张海龙; 谭国平; 续斌
Original assignee: ZTE Corp
Current assignee: ZTE Corp
Priority date: 2003-01-30
Filing date: 2003-01-30
Publication date: 2007-11-28
Anticipated expiration: 2023-01-30
Also published as: CN1521516A

Abstract

The present invention relates to a method for obtaining GPS time on a single board in a code division multiple access system. The present invention comprises the steps that a GPS clock signal obtained by the single board only has a clock signal having a pulse every N seconds (PPNS) and the current time, wherein N is any number of natural numbers smaller than 10, PPNS is sent once at the boundary of every N seconds, a current time message is sent closely behind the PPNS clock signal, the parameter of the message is the GPS time corresponding to the last PPNS clock signal, and the unit of the time is M millisecond; when application layer software receives the current time message, the value of a first memory is set to the sum of the parameter of the current message and N*1000/M; when the next PPNS clock signal is interrupted, the operation that a second memory is equal to the first memory is carried out; in N seconds, M millisecond signals which are synchronous with the GPS clock and are produced by hardware are counted; the GPS time of the current single board is determined according to the sum of the value stored in the second memory and the count value in the counter when N seconds are over.

Description

The production method of accurate GPS time of veneer

Technical field

The present invention relates on veneer, obtain in CDMA (hereinafter to be referred as the CDMA) system a kind of method of accurate GPS (hereinafter to be referred as GPS) time, particularly relate to a kind of method that on veneer, obtains accurate gps time in the cdma system that is accurate to Millisecond.

Background technology

The application layer software of some veneers in the cdma system need be inquired about accurate gps time, application layer software such as vocoder/selector switch (hereinafter to be referred as SVM) veneer requires to have the frame number synchronous with gps time in the forward direction voice packet that sends, markov needs to produce with the synchronous markov packet of gps time in calling out, and this requires application layer software can inquire about current accurate gps time at any time.Therefore, on the SVM veneer, must provide a kind of method to be used to obtain accurate gps time.In cdma system, the gps clock signal that obtains on a lot of veneers be per two seconds a pulse (hereinafter to be referred as PP2S) interrupt, promptly idol second is interrupted, the Current GPS time of obtaining on the veneer can only be accurate to a second level.And application layer software requires must require to be accurate to Millisecond to gps time on this veneer, only relies on an idol second signal obviously can not reach this requirement.

Summary of the invention

Can not be accurate to the problem of Millisecond at prior art from the Current GPS time that veneer obtains, the present invention proposes the veneer production method of accurate GPS time.

A kind of accurate GPS time method that obtains on veneer in code division multiple access system provided by the invention comprises the steps:

(1) make the gps clock signal that obtains on the veneer have only (the being designated hereinafter simply as PPNS) clock signal and the current time of every pulse N second, N is natural any one number less than 10, described every pulse N second is accurate timing pip, send once on every N border second, be not with parameter, current time message is immediately following sending after the clock signal of described every pulse N second, and its parameter is the gps time of the clock signal correspondence of last every pulse N second, and chronomere is the M millisecond;

(2) receive that at application layer software the current time makes during message the value of first memory be set to the parameter and the N * 1000 ÷ M sums of current time message, the number of pairing M millisecond was interrupted in the value representative of set first memory at 0 o'clock in 0 minute 0 second on January 1st, 1980 to the clock signal of a pulse every N of next one second from the gps time true origin;

(3) when the clock signal of a pulse every N of next one second is interrupted, carry out the operation of second memory=first memory;

(4) select a counter for use, when the clock signal of a pulse every N second is interrupted,, in second the M millisecond signal that is synchronized with gps clock that is produced by hardware is counted at described N to counter O reset;

(5) gps time that is defined as current single board according to the value of storing in the second memory when described N finishes second and the count value sum in the counter.

And when N is 2 and M when being 1.25, the gps time that is obtained can be accurate to 1.25 milliseconds.

In addition, described veneer can be vocoder/selector module; Described method can be used for reading gps time in the markov call testing.

Adopt the accurate GPS time of above-mentioned veneer proposed by the invention to produce the concrete many advantages of way.For example, can obtain current accurate gps time, but degree of accuracy M millisecond, and when M was 1.25 milliseconds, the gps time that is obtained can be accurate to 1.25 milliseconds; Application layer software just can be inquired about the current GPS time at any time through set register sum counter among visit the present invention, and is very convenient; In cdma system, obtain accurate gps clock and have considerable meaning, there is not accurate gps clock signal, cdma system just can not normal operation.So the present invention not only provides necessary demand to SVM veneer application layer software, and the overall operation of cdma system is all had very important significance.

Description of drawings

From below in conjunction with the explanation of accompanying drawing to embodiment, advantage of the present invention and purpose will become clear more and be more readily understood.

Fig. 1 represents the process flow diagram of an embodiment of the inventive method.

Embodiment

According to the present invention, in code division multiple access system, on veneer, obtain to have adopted the PPNS clock signal and current time (hereinafter to be referred as the TOD) message that make the gps clock signal that obtains on the veneer have only every pulse N second in the accurate GPS time method.N is natural any one number less than 10, and PPNS is accurate timing pip, sends once on every N border second, is not with parameter.Current time message is immediately following sending after the clock signal of PPNS, and its parameter is the gps time of a last PPNS clock signal correspondence, if chronomere is the M millisecond, is N * 1000 ÷ M then and in the number of N corresponding M millisecond in second.Therefore, method of the present invention comprises the steps:

(1) make the gps clock signal that obtains on the veneer have only the clock signal and the current time of every pulse N second, N is natural any one number less than 10, send once on every N border second, be not with parameter, current time message is immediately following sending after the clock signal of described every pulse N second, its parameter is the gps time of last every N pulse second (PPNS) clock signal correspondence, chronomere is the M millisecond, and promptly the parametric representation of current time message is from the gps time true origin number of 0: 0: 0 on the 1st January in 1980 to pairing M millisecond of current time;

(2) receive that at application layer software the current time makes during message the value of first memory be set to the parameter and the N * 1000 ÷ M sums of current time message, the number of pairing M millisecond was interrupted in representative at 0 o'clock in 0 minute 0 second on January 1st, 1980 to the clock signal of a pulse every N of next one second from the gps time true origin;

When being 2 seconds below in conjunction with 1 couple of N of the present invention of accompanying drawing and the embodiment of M when being 1.25 milliseconds be elaborated.When N is 2 seconds and M when being 1.25 milliseconds, promptly, when the gps clock signal that obtains on the veneer has only per two seconds pulse (hereinafter to be referred as PP2S) clock signal and TOD message, PP2S is accurate timing pip, each idol second border sends a PP2S, be not with parameter, TOD message is immediately following sending behind PP2S, its parameter is the gps time of a last PP2S signal correspondence, unit is 1.25 milliseconds, in other words the parametric representation of current time message from gps time true origin 0: 0: 0 on the 1st January in 1980 to pairing 1.25 milliseconds number of current time.1.25 milliseconds number corresponding in 2 seconds is 2 * 1000 ÷ 1.25=1600.In the case, the gps time that is obtained can be accurate to 1.25 milliseconds.Specifically, in the case, of the present inventionly in code division multiple access system, on veneer, obtain accurate GPS time method, comprise the steps:

(1) make the gps clock signal that obtains on the veneer have only the clock signal and the current time message of a pulse in per 2 seconds, pulse in per 2 seconds is accurate timing pip, send once on each idol second border, be not with parameter, current time message is immediately following sending after the clock signal of a pulse in per 2 seconds, its parameter is the gps time of the clock signal correspondence of a last pulse in per 2 seconds, and unit is 1.25 milliseconds;

(2) select two storeies for use, the first memory note is A, and the second memory note is B, is used for writing down the gps time of PP2S signal correspondence; Receive that at application layer software the current time makes during message the value of first memory A be set to parameter and 1600 (2 * 1000 ÷ 1.25) sum of current time message, representative was interrupted pairing 1.25 milliseconds number to the clock signal of a next one pulse in per 2 seconds 0: 0: 0 on the 1st January in 1980 from the gps time true origin;

(3) when the clock signal of a next one pulse in per 2 seconds is interrupted, carry out the operation of second memory B=first memory A;

(4) select a counter for use, when the clock signal of a pulse in per 2 seconds is interrupted,, in described 2 seconds, the 1.25 milliseconds of signals that are synchronized with gps clock that produced by hardware are counted counter O reset;

(5) determine the gps time of current single board according to the count value sum in value of storing in the second memory and the counter.The present invention has obtained successful application in the markov call testing.In the markov call testing, at first require transmitting terminal and receiving end can carry out clock synchronization, and before the initialization of the moment of clock synchronization reverse pseudo-random sequence generator.Be example with the forward direction pseudo-random sequence generator below, the concrete application of the present invention in the markov call testing is described.

The markov detailed process sees also that application number is 01126455.1, name is called the patent document of " markov is called out the method that pseudo-random sequence produces ".In markov is called out, base station controller is Electronic Serial Number (Electronic SerialNumber) ESN that sends of storing mobile station (Mobile Starion) MS at first, read the current GPS time every 20 milliseconds then, this time is changed the back according to certain algorithm to be compared with the ESN that stores, satisfy certain condition and think that then the forward direction pseudo-random sequence generator of transfer table and base station side is upward synchronous, utilize this time just can constantly produce required synchronous markov pseudo-random sequence then, and produce the markov packet, thereby carry out the monitoring of effective forward service link quality.Read gps time here and just used the method that the present invention proposes.

Claims

1, a kind ofly in code division multiple access system, on veneer, obtains accurate GPS time method, comprise the steps:

(1) make the gps clock signal that obtains on the veneer have only the clock signal and the current time of every pulse N second, N is natural any one number less than 10, described every pulse N second is accurate timing pip, send once on every N border second, be not with parameter, current time message is immediately following sending after the clock signal of described every pulse N second, and its parameter is the gps time of the clock signal correspondence of last every pulse N second, and chronomere is the M millisecond;

(5) gps time of determining current single board according to the value of storing in the second memory when described N finishes second and the count value sum in the counter.

2, the method for claim 1 is characterized in that, described N is 2, and described M is 1.25.

3, the method for claim 1 is characterized in that described veneer is vocoder/selector module.

4, the method for claim 1 is characterized in that described method is used for the markov call testing and reads gps time.