CN201555591U

CN201555591U - Direct-current sine-cosine azimuth indicator

Info

Publication number: CN201555591U
Application number: CN2009202934759U
Authority: CN
Inventors: 张凉; 罗宜周; 曾芹
Original assignee: Shanghai Kaidike Aviation Engineering Technology Co Ltd
Current assignee: Shanghai Kaidike Aviation Engineering Technology Co Ltd
Priority date: 2009-12-18
Filing date: 2009-12-18
Publication date: 2010-08-18
Anticipated expiration: 2019-12-18

Abstract

The utility model relates to a direct-current sine-cosine azimuth indicator comprising a PC104 embedding type system and a BCD code display meter; the PC104 embedding type system comprises an analogue/digital acquisition module, a microprocessor module and a digital interface module; the analogue/digital acquisition module, the microprocessor module, the digital interface module and the BCD code display meter are connected in sequence. Compared with the prior art, the direct-current sine-cosine azimuth indicator has the advantages of high accuracy and resolution, small testing error and the like.

Description

A kind of direct current sine and cosine azimuth indicator

Technical field

The utility model relates to a kind of azimuth indicator, especially relates to a kind of direct current sine and cosine azimuth indicator.

Background technology

Wireless compass is to be used for airborne short-range aids into the aircraft flight orientation, and when being operated in the compass mode, its receives the signal of guidance station, provides the relative orientation of the guidance station that is received, and vector aircraft on-course or the flight of marching into the arena.Common output bearing signal has several modes at present, comprises exchanging three-phase synchronous signal, direct current sine and cosine bearing signal, digitally encoded signal (as ARINC429, GJB289A coded signal) etc.

Wherein direct current sine and cosine bearing signal as shown in Figure 1.Either party's place value of wireless compass output all can be represented by the two-way d. c. voltage signal, is respectively direct current sinusoidal signal and direct current cosine signal.

When the performance of test wireless compass, corresponding testing apparatus need be measured the bearing signal of its output.As parts of testing apparatus, direct current sine and cosine azimuth indicator is used to refer to the direct current sine and cosine bearing signal of wireless compass output.

Seen in the market direct current sine and cosine azimuth indicator adopts pure mimic channel to realize that precision is low, and error is bigger, and calibration is inconvenient.

Summary of the invention

The purpose of this utility model is exactly that a kind of precision and resolution height, direct current sine and cosine azimuth indicator that test error is little are provided in order to overcome the defective that above-mentioned prior art exists.

The purpose of this utility model can be achieved through the following technical solutions:

A kind of direct current sine and cosine azimuth indicator, it is characterized in that, this indicator comprises PC104 embedded system, binary-coded decimal digital display meter, described PC104 embedded system comprises mould/number acquisition module, microprocessor module, digital interface module, and described mould/number acquisition module, microprocessor module, digital interface module, binary-coded decimal digital display meter connect successively.

Described mould/number acquisition module, digital interface module are integrated on the AD plate of PC104 embedded system.

Described microprocessor module is the CPU board of PC104 embedded system.

Compared with prior art, the utlity model has following advantage:

Precision and resolution height, test error is little, and calibration is convenient.

Description of drawings

Fig. 1 is the direct current sine and cosine bearing signal figure of a kind of direct current sine and cosine of the utility model azimuth indicator;

Fig. 2 is the structural representation of a kind of direct current sine and cosine of the utility model azimuth indicator;

Fig. 3 is the workflow diagram of the PC104 embedded system of a kind of direct current sine and cosine of the utility model azimuth indicator.

Embodiment

Below in conjunction with the drawings and specific embodiments the utility model is elaborated.

Embodiment

As shown in Figure 2, a kind of direct current sine and cosine azimuth indicator, this indicator comprises PC104 embedded system, binary-coded decimal digital display meter 24, described PC104 embedded system comprises mould/number acquisition module 21, microprocessor module 22, digital interface module 23, and described mould/number acquisition module 21, microprocessor module 22, digital interface module 23, binary-coded decimal digital display meter 24 connect successively.Described mould/number acquisition module 21 is converted to digital signal with the direct current sine and cosine bearing signal of importing and sends into

microprocessor module

22,22 pairs of digital signals of this microprocessor module are tested, and be converted into 8421BCD sign indicating number form, output to digital interface module 23, digital interface module 23 arrives binary-coded decimal digital display meter 24 with the digital data transmission of binary-coded decimal form, and this binary-coded decimal digital display meter 24 shows.

As shown in Figure 3, described PC104 embedded system is as follows to the input signal processing procedure:

Step 1 starts the PC104 embedded system, begins test;

Step 2, mould/number acquisition module start an A/D conversion, and direct current sinusoidal signal analog quantity is converted to digital quantity, and value is designated as SIN;

Step 3, mould/number acquisition module start another time A/D conversion, and direct current cosine signal analog quantity is converted to digital quantity, and value is designated as COS;

Whether step 4, microprocessor module judge SIN, COS all less than default threshold value, if yes, then think and continue the no signal input to wait for, return step 1, if otherwise execution in step 5;

Step 5, microprocessor module judgment value SIN whether less than its peaked half, if enter step (6), otherwise enter step 7;

Step 6, microprocessor module carries out the arc tangent conversion to the ratio of SIN/COS, the value of obtaining θ, the symbol according to SIN and COS draws orientation values again:

If SIN＞0, COS＞0, then orientation values is θ;

If SIN＞0, COS＜0, then orientation values is π+θ;

If SIN＜0, COS＜0, then orientation values is π+θ;

If SIN＜0, COS＞0, then orientation values is 2 π+θ;

And execution in step 8;

Step 7, microprocessor module carries out the arc cotangent conversion to the ratio of COS/SIN, the value of obtaining θ, the symbol according to SIN and COS draws orientation values again:

If SIN＞0, COS＞0, then orientation values is θ;

If SIN＞0, COS＜0, then orientation values is θ;

If SIN＜0, COS＜0, then orientation values is π+θ;

If SIN＜0, COS＞0, then orientation values is π+θ;

Execution in step 8;

Step 8 deposits the orientation values that obtains in buffer memory, and sampling number adds 1, and enters step 9;

Step 9 judges whether sampling number reaches setting value 100, then continues sampling if not, returns step 1, if then enter step 10;

Step 10 with the sampling number zero clearing, enters step 11;

Step 11 is carried out digital filtering to the orientation values in the buffer memory, obtains filtered orientation values, enters step 12;

Step 12 is converted to 8421BCD sign indicating number form with the orientation values that obtains and exports to the digital interface module, finishes once test, and returns step 1 and carry out repeated test.

The function of mould/number acquisition module 21 and digital interface module 23 is realized by PC104 AD plate (model is ADT-700), the function of microprocessor module 22 realizes that by PC104 CPU board (model is 6231-100-16M) function of binary-coded decimal digital display meter is realized by 4 binary-coded decimal digital display meters (model is XL-BCD-4).

Claims

1. direct current sine and cosine azimuth indicator, it is characterized in that, this indicator comprises PC104 embedded system, binary-coded decimal digital display meter, described PC104 embedded system comprises mould/number acquisition module, microprocessor module, digital interface module, and described mould/number acquisition module, microprocessor module, digital interface module, binary-coded decimal digital display meter connect successively.

2. a kind of direct current sine and cosine azimuth indicator according to claim 1 is characterized in that described mould/number acquisition module, digital interface module are integrated on the AD plate of PC104 embedded system.

3. a kind of direct current sine and cosine azimuth indicator according to claim 1 is characterized in that described microprocessor module is the CPU board of PC104 embedded system.