Method for generating bipolar differential Manchester code signal jitter based on non-return-to-zero code

Abstract

The invention discloses a method for generating bipolar differential Manchester coded data based on a non-return-to-zero code, and belongs to the field of avionics metering calibration. The invention discloses a method for generating bipolar differential Manchester encoding data based on a non-return-to-zero code, which comprises the following steps of: generating bipolar differential Manchester encoding through multi-channel superposition and inter-channel synchronous combination by utilizing a non-return-to-zero code pattern generation function provided by a pulse code pattern signal generator; on the basis of a method for generating bipolar differential Manchester coded data based on a non-return-to-zero code, a bipolar differential Manchester code with a period of T is split into 2N non-return-to-zero waveforms, wherein the first N high-level non-return-to-zero waveforms with periods of T / 2N and the last N low-level non-return-to-zero waveforms with periods of T / 2N are high-level non-return-to-zero waveforms with periods of T / 2N; by adjusting the number of high-level and low-level non-return-to-zero waveforms, the position of a bipolar differential Manchester encoding zero crossing point, namely Manchester encoding data signal jitter, is adjusted; by adjusting the size of N, the resolution of the zero crossing point position can be adjusted, signal jitter of any data bit can be realized, and the method is used for the limit parameter adaptability test of the serial data bus receiver.

Description

Technical Field

[0001] The present invention relates to a simulation method for realizing the jitter of bipolar differential Manchester - encoded data signals based on unipolar non - return - to - zero codes, and belongs to the field of avionics metrology and calibration. Background Art

[0002] In the field of avionics data bus calibration, during the calibration of serial data bus test equipment with Manchester - encoded data information such as 1553B and ARINC664, it is necessary to change waveform parameters such as the data transmission rate, signal amplitude, rise time, fall time, and zero - crossing position of the data signal, so as to generate controllable known distortions in the bus data signal for testing the sensitivity and limit parameter adaptability of the bus receiver. Among them, parameters such as the data transmission rate, signal amplitude, rise time, and fall time can be adjusted by directly setting and combining to generate the electrical characteristic parameters of the non - return - to - zero code of Manchester encoding; while the zero - crossing position needs to be realized by the method described in this patent. Summary of the Invention

[0003] One of the purposes of the present invention is to provide a method for generating bipolar differential Manchester - encoded data based on non - return - to - zero codes. By using the non - return - to - zero code generation function provided by a pulse code pattern generator, bipolar differential Manchester encoding is generated through multi - channel superposition and inter - channel synchronous combination, and the zero - crossing position of the generated bipolar differential Manchester - encoded signal can be arbitrarily adjusted.

[0004] The second purpose of the present invention is to provide a method for realizing the jitter of bipolar differential Manchester - encoded data signals on the basis of the method for generating bipolar differential Manchester - encoded data based on non - return - to - zero codes, to realize the signal jitter of any data bit for testing the limit parameter adaptability of serial data bus receivers.

[0005] The purpose of the present invention is realized through the following technical solutions:

[0006] The method for generating bipolar differential Manchester - encoded data based on non - return - to - zero codes disclosed by the present invention includes the following steps:

[0007] Step 1: The channel 1 of the pulse code pattern generator outputs a waveform with a period of T, the waveform amplitude of the first half - period is a high - level non - return - to - zero waveform of +V / 4, and the waveform amplitude of the second half - period is a low - level non - return - to - zero waveform of -V / 4; the channel 2 synchronously outputs a waveform with a period of T, the waveform amplitude of the first half - period is a low - level non - return - to - zero waveform of -V / 4, and the waveform amplitude of the second half - period is a high - level non - return - to - zero waveform of +V / 4; the two non - return - to - zero waveforms are differentially superimposed and synchronously output to obtain a waveform A with an amplitude of ±V / 2.

[0008] Step 2: Channel 3 of the pulse pattern generator outputs a waveform with a period of T. The waveform amplitude in the first half of the period is a low-level non-return-to-zero waveform of -V / 4, and the waveform amplitude in the second half of the period is a high-level non-return-to-zero waveform of +V / 4. Channel 4 synchronously outputs a waveform with a period of T. The waveform amplitude in the first half of the period is a high-level non-return-to-zero waveform of +V / 4, and the waveform amplitude in the second half of the period is a low-level non-return-to-zero waveform of -V / 4. The two non-return-to-zero waveforms are differentially superimposed and synchronously output to obtain a waveform B with an amplitude of ±V / 2.

[0009] Step 3: The waveform A obtained in Step 1 and the waveform B obtained in Step 2 are differentiated to generate bipolar differential Manchester encoded data with a period of T and a waveform amplitude of ±V.

[0010] Based on the method for generating bipolar differential Manchester encoded data based on non-return-to-zero codes, the present invention also discloses a method for realizing jitter of bipolar differential Manchester encoded data signals, including the following steps:

[0011] Step 1: Channel 1 of the pulse pattern generator outputs N high-level waveforms with a period of T / 2N and N low-level waveforms with a period of T / 2N. Channel 2 outputs N low-level non-return-to-zero waveforms with a period of T / 2N and N high-level non-return-to-zero waveforms with a period of T / 2N. The two non-return-to-zero waveforms are superimposed and synchronously output to obtain a waveform A.

[0012] Step 2: Channel 3 of the pulse pattern generator outputs N low-level non-return-to-zero waveforms with a period of T / 2N and N high-level non-return-to-zero waveforms with a period of T / 2N. Channel 4 outputs N high-level non-return-to-zero waveforms with a period of T / 2N and N low-level non-return-to-zero waveforms with a period of T / 2N. The two non-return-to-zero waveforms are superimposed and synchronously output to obtain a waveform B.

[0013] Step 3: The waveform A obtained in Step 1 and the waveform B obtained in Step 2 are differentiated to generate the final bipolar differential Manchester encoded data.

[0014] Step 4: Select any coding position to adjust the zero-crossing position. When it is necessary to shift the zero-crossing to the left cycles and x ≤ (N - 1), adjust the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B to N - x, and at the same time adjust the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B to N + x. Then the zero-crossing position of the final bipolar differential Manchester encoding moves to the left by cycles. Conversely, when it is necessary to shift the zero-crossing to the right When there are N periods and y ≤ (N - 1), adjust the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B to be N + y, and at the same time adjust the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B to be N - y. Then the zero-crossing position of the final bipolar differential Manchester code moves to the right by N periods; by adjusting the value of N, the resolution of the zero-crossing position is adjusted, and finally the jitter of the bipolar differential Manchester-coded data signal is achieved.

[0015] Beneficial effects:

[0016] 1. A method for generating bipolar differential Manchester-coded data based on non-return-to-zero codes disclosed in the present invention utilizes the non-return-to-zero code generation function provided by a pulse code pattern generator. By multi-channel superposition and inter-channel synchronous combination, bipolar differential Manchester codes are generated, and the zero-crossing position is adjusted by combining multiple (2N) non-return-to-zero codes to generate one bipolar differential Manchester code.

[0017] 2. The method for realizing the jitter of the bipolar differential Manchester-coded data signal disclosed in the present invention, on the basis of achieving beneficial effect 1, selects any coding position to adjust the zero-crossing position: when it is necessary to move the zero-crossing to the left by N periods and x ≤ (N - 1), adjust the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B to be N - x, and at the same time adjust the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B to be N + x. Then the zero-crossing position of the final bipolar differential Manchester code moves to the left by N periods; conversely, when it is necessary to move the zero-crossing to the right by N periods and y ≤ (N - 1), adjust the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B to be N + y, and at the same time adjust the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B to be N - y. Then the zero-crossing position of the final bipolar differential Manchester code moves to the right by N periods; by adjusting the value of N, the resolution of the zero-crossing position can be adjusted.

[0018] 3. The method for realizing the jitter of the bipolar differential Manchester-coded data signal disclosed in the present invention realizes the signal jitter of any data bit in the data frame and is used for the limit parameter adaptability test of the serial data bus receiver.

[0019] 4. The method for realizing the jitter of bipolar differential Manchester-coded data signals disclosed in the present invention can, while realizing signal jitter, adjust waveform period, waveform high and low levels, and waveform transition time, so as to achieve waveform parameters such as the data transmission rate, signal amplitude, rise time, and fall time of Manchester coding, and is used for the limit parameter adaptability test of serial data bus receivers. Description of the Drawings

[0020] Figure 1 Schematic diagram of the waveform of the positive terminal A of the differential Manchester-coded signal;

[0021] Figure 2 Schematic diagram of the waveform of the negative terminal B of the differential Manchester-coded signal;

[0022] Figure 3 Waveform A and waveform B are differentially generated into bipolar Manchester coding;

[0023] Figure 4 Schematic diagram of the zero-crossing position of any bit of the bipolar differential Manchester coding shifted 0.1 μs to the left;

[0024] Figure 5 Schematic diagram of the zero-crossing position of any bit of the bipolar differential Manchester coding shifted 0.3 μs to the right. Detailed Embodiment

[0025] To better illustrate the purpose and advantages of the present invention, the following further describes the content of the invention with reference to the drawings and examples.

[0026] Embodiment Example:

[0027] The method for realizing the jitter of bipolar differential Manchester-coded data signals disclosed in this embodiment example is used to realize the jitter of bipolar differential Manchester-coded data signals of 1 Mbps on a 1553B bus. The waveform period T is 1 μs, and the non-return-to-zero waveform 2N is 10, that is, N is 5:

[0028] Step 1. As Figure 1 shown, channel 1 of the pulse pattern generator outputs a waveform with a period of 1 μs. The first half of the period is a non-return-to-zero high-level waveform with a waveform amplitude of +V / 4 for 5 0.1-μs waveforms, and the second half of the period is a non-return-to-zero low-level waveform with a waveform amplitude of -V / 4 for 5 0.1-μs waveforms; channel 2 synchronously outputs a waveform with a period of 1 μs. The first half of the period is a non-return-to-zero low-level waveform with a waveform amplitude of -V / 4 for 5 0.1-μs waveforms, and the second half of the period is a non-return-to-zero low-level waveform with a waveform amplitude of +V / 4 for 5 0.1-μs waveforms; the two non-return-to-zero waveforms are superimposed and synchronously output to obtain a waveform A with an amplitude of ±V / 2;

[0029] Step 2. As Figure 2As shown, the output of channel 3 of the pulse code pattern generator is a waveform with a period of 1 μs. The first half of the period is a low-level non-return-to-zero waveform with a waveform amplitude of -V / 4 for 5 waveforms of 0.1 μs each, and the second half of the period is a low-level non-return-to-zero waveform with a waveform amplitude of +V / 4 for 5 waveforms of 0.1 μs each; channel 4 synchronously outputs a waveform with a period of 1 μs. The first half of the period is a high-level non-return-to-zero waveform with a waveform amplitude of +V / 4 for 5 waveforms of 0.1 μs each, and the second half of the period is a low-level non-return-to-zero waveform with a waveform amplitude of -V / 4 for 5 waveforms of 0.1 μs each; the two non-return-to-zero waveforms are superimposed and synchronously output to obtain waveform B with an amplitude of ±V / 2;

[0030] Step three, as Figure 3 shown, the waveform A obtained in step one and the waveform B obtained in step two are differentiated to generate 1553B bus bipolar differential Manchester encoded data;

[0031] Step four, as Figure 4 shown, shift the zero-crossing position of any bipolar differential Manchester encoded data 0.1 μs to the left: adjust the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B to be 4 waveforms of 0.1 μs in period, and at the same time adjust the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B to be 6 waveforms of 0.1 μs in period, then the zero-crossing position of the 1553B bus bipolar differential Manchester encoding moves 0.1 μs to the left, that is, the data signal jitters 0.1 μs to the left;

[0032] Similarly, as Figure 5 shown, realize the zero-crossing moving 0.3 μs to the right: adjust the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B to be 8 waveforms of 0.1 μs in period, and at the same time adjust the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B to be 2 waveforms of 0.1 μs in period, then the zero-crossing position of the 1553B bus bipolar differential Manchester encoding moves 0.3 μs to the right, that is, the data signal jitters 0.3 μs to the right.

[0033] The above specific description further details the purpose, technical solution, and beneficial effects of the invention. It should be understood that the above is only a specific embodiment of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for generating bipolar differential Manchester coded data based on non-return-to-zero code, characterized in that: The following steps are included: Step 1, the pulse pattern generator channel 1 outputs a waveform with a period of T, wherein the waveform amplitude of the first half of the period is a high-level non-return-to-zero waveform of +V / 4, and the waveform amplitude of the second half of the period is a low-level non-return-to-zero waveform of -V / 4; channel 2 synchronously outputs a waveform with a period of T, wherein the waveform amplitude of the first half of the period is a low-level non-return-to-zero waveform of -V / 4, and the waveform amplitude of the second half of the period is a high-level non-return-to-zero waveform of +V / 4; the two non-return-to-zero waveforms are differentially superimposed and synchronously output to obtain a waveform A with an amplitude of ±V / 2; Step 2, channel 3 of the pulse pattern generator outputs a waveform with a period of T, wherein the waveform amplitude of the first half of the period is a low-level non-return-to-zero waveform with a amplitude of -V / 4, and the waveform amplitude of the second half of the period is a high-level non-return-to-zero waveform with a amplitude of +V / 4; channel 4 synchronously outputs a waveform with a period of T, wherein the waveform amplitude of the first half of the period is a high-level non-return-to-zero waveform with a amplitude of +V / 4, and the waveform amplitude of the second half of the period is a low-level non-return-to-zero waveform with a amplitude of -V / 4; the two non-return-to-zero waveforms are differentially superimposed and synchronously output to obtain a waveform B with an amplitude of ±V / 2; Step 3: Differentiate waveform A obtained in step 1 and waveform B obtained in step 2 to generate bipolar differential Manchester coded data with a period of T and a waveform amplitude of ±V.

2. A method for implementing bipolar differential Manchester coded data signal jitter based on the method of claim 1, characterized in that: The following steps are included: Step 1, channel 1 of the pulse pattern generator outputs a high-level waveform with N periods of T / 2N and a low-level waveform with N periods of T / 2N; channel 2 outputs a low-level non-return-to-zero waveform with N periods of T / 2N and a high-level non-return-to-zero waveform with N periods of T / 2N; the two non-return-to-zero waveforms are superimposed and output synchronously to obtain waveform A; Step 2, channel 3 of the pulse pattern generator outputs N low-level non-return-to-zero waveforms with a period of T / 2N and N high-level non-return-to-zero waveforms with a period of T / 2N; channel 4 outputs N high-level non-return-to-zero waveforms with a period of T / 2N and N low-level non-return-to-zero waveforms with a period of T / 2N; the two non-return-to-zero waveforms are superimposed and output synchronously to obtain waveform B; Step 3: Differentiate the waveform A obtained in step 1 and the waveform B obtained in step 2 to generate final bipolar differential Manchester coded data; Step 4: Select any encoding position to adjust the zero position: When the zero point needs to be moved left When there are N cycles and x≤(N-1), the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B are adjusted to Nx, and the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B are adjusted to N+x. Then the zero-crossing point position of the final bipolar differential Manchester encoding moves to the left. cycles; On the contrary, when it is necessary to move right through the zero point When there are N+y cycles and y≤(N-1), the high-level non-return-to-zero waveform of waveform A and the low-level non-return-to-zero waveform of waveform B are adjusted to N+y, and the low-level non-return-to-zero waveform of waveform A and the high-level non-return-to-zero waveform of waveform B are adjusted to Ny. Then the zero-crossing point position of the final bipolar differential Manchester encoding moves to the right. cycles; by adjusting the size of N, the resolution of the zero-crossing position is adjusted, and finally the bipolar differential Manchester encoded data signal jitter is achieved.

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