CN117176295A - Manchester code receiving and decoding method and device - Google Patents

Abstract

The application provides a method and a device for receiving and decoding Manchester codes, and relates to the technical field of data receiving and decoding. The method comprises the following steps: receiving valid data; generating a detection clock signal according to the effective data transmission rate; detecting effective data in a detection window set on a time axis according to a detection clock signal; wherein the detection window only partially covers the valid data duration. The method avoids the detection of too many and too dense windows, also avoids the detection of a plurality of windows and the detection of the same 1-bit signal bit, and reduces the hardware cost. And each bit can be sampled without oversampling, so that the reliability is ensured.

Description

Manchester code receiving and decoding method and device

Technical Field

The application relates to the technical field of receiving and decoding data transmission, in particular to a method and a device for receiving and decoding Manchester codes.

Background

Digital signal encoding is intended to solve the problem of digital signal representation of digital data, i.e. representing data by encoding a digital signal. The digital signal coding work is generally completed by hardware, and the following three coding methods are commonly used: non return to zero code, manchester encoding, differential Manchester encoding. The present application is focused on the latter two.

Manchester encoding is commonly used for local area network transmissions. In Manchester encoding, a transition exists in the middle of each bit, and the transition in the middle of the bit is used as a clock signal and a data signal; the high-to-low transition represents "0" and the low-to-high transition represents "1", as in fig. 1, with the following two-point law:

1. at an intermediate time of a period of one bit: a 1 is represented from low to high (i.e., up transitions or rising edges) and a 0 is represented from high to low (i.e., down transitions or falling edges);

2. at the moment of bit-to-bit boundary: when 1 is continuous, the down jump occurs; at consecutive 0 s, an up-jump occurs.

Still another is differential Manchester encoding, where transitions in the middle of each bit provide only clock timing, and where each bit starts with or without transitions to indicate a "0" or "1", with transitions to "0", and no transitions to "1".

The existing Manchester code receiving and decoding method is used for detecting the whole effective data transmission time period and oversampling, and ensures the reliability of the data, but has higher consumption on hardware.

Therefore, how to ensure reliability and reduce hardware cost is a technical problem to be solved.

Disclosure of Invention

The application aims to provide a method and a device for receiving and decoding Manchester codes, which are used for solving the technical problems of ensuring reliability and reducing hardware cost in the prior art.

In order to achieve the above purpose, the following technical scheme is adopted in the embodiment of the application.

In a first aspect, an embodiment of the present application provides a method for receiving and decoding a manchester code, including:

receiving valid data;

generating a detection clock signal according to the effective data transmission rate;

detecting effective data in a detection window set on a time axis according to a detection clock signal; wherein the detection window only partially covers the valid data duration.

Optionally, the step of generating the detection clock signal according to the effective data transmission rate comprises:

and generating a detection clock signal with a set frequency according to the effective data transmission rate stored in the register or the nonvolatile memory.

Optionally, before the step of generating the detection clock signal according to the effective data transmission rate, or before the step of receiving the effective data, the method further comprises:

receiving a data head, wherein the data head carries transmission rate information of effective data;

and analyzing the effective data transmission rate information in the data head.

Optionally, the data header contains a data header end identifier to characterize the end of the data header and the beginning of valid data.

Optionally, the data of the data head except the data head end mark adopts high-low level periodic alternating distribution, and the transmission rate information of the effective data is carried by using the duration time of each high level or low level.

Optionally, the step of receiving the data header is preceded by the step of receiving valid data, and the step of receiving the data header includes: determining the amplification factor according to the voltage difference between the high level and the low level in the data head, and amplifying the signal of the data head;

the step of receiving valid data includes: and amplifying the signal of the effective data according to the amplification factor.

In a second aspect, an embodiment of the present application provides a receiving and decoding apparatus for a manchester code, including:

the clock module is used for generating a detection clock signal according to the effective data transmission rate;

the window detection module is used for receiving the effective data and detecting the effective data according to the detection clock signal through a detection window set on a time axis; wherein the detection window only partially covers the valid data duration.

Optionally, the receiving and decoding device of the manchester code further includes:

a register or nonvolatile memory for storing an effective data transfer rate;

the clock module is used for generating a detection clock signal with a set frequency according to the effective data transmission rate stored in the register or the nonvolatile memory.

Optionally, the receiving and decoding device of the manchester code further includes:

the rate detection module is used for receiving the data head, the data head carries the transmission rate information of the effective data, and the effective data transmission rate information in the data head is analyzed.

Optionally, the window detection module includes:

the amplifying module is used for determining the amplification factor according to the voltage difference between the high level and the low level in the data head, amplifying the signal of the effective data and outputting an amplified signal;

the generating module is used for generating a clock trigger signal according to the detection clock signal;

and the D trigger module is used for generating output data according to the clock trigger signal and the amplified signal.

Optionally, the amplifying module is configured to receive an enable signal, amplify the signal of the valid data under an enable condition, and output an amplified signal to the D flip-flop module;

the generation module is used for generating a clock trigger signal and an enabling signal according to the detection clock signal and the size of the detection window, and the enabling signal is earlier than the clock trigger signal so as to ensure that the D trigger module is set according to the amplifying signal when receiving the clock trigger signal.

Compared with the prior art, the application has the following beneficial effects:

according to the Manchester code receiving and decoding method and device, effective data are detected through the detection windows set on the time axis, wherein each set window corresponds to 1-bit effective data. The method avoids excessive and intensive detection, also avoids repeated detection of the same 1-bit effective data, and reduces hardware cost. And each bit can be sampled without oversampling, so that the reliability is ensured.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic diagram of a receiving and decoding method of manchester codes according to an embodiment of the present application;

FIG. 2 is a schematic diagram of two types of data headers, valid data, and windows on a time axis according to an embodiment of the present application;

fig. 3 is a schematic diagram of a receiving and decoding device of manchester codes according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a receiving and decoding device for Manchester code using a memory to store window size and data rate according to an embodiment of the present application;

fig. 5 is a schematic diagram of a receiving and decoding device of manchester code for determining a window size and a data rate by using a rate detection module according to an embodiment of the present application;

fig. 6 is a schematic diagram of a window detection module according to an embodiment of the present application;

FIG. 7 is a schematic diagram of a processing method of differential Manchester encoding according to an embodiment of the present application;

fig. 8 is a schematic diagram of a differential manchester encoded data receiving and decoding apparatus according to an embodiment of the present application.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and the described embodiments are some embodiments of the present application, but not all embodiments of the present application. The components of the embodiments of the present application generally described in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the application, as presented in the figures, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application. The following embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present application, it should be noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The term "coupled" is to be interpreted broadly, as being a fixed connection, a removable connection, or an integral connection, for example; can be directly connected or indirectly connected through an intermediate medium.

The existing Manchester encoding and decoding needs over-sampling, and a high-frequency clock or a multi-phase clock is needed, so that extra power consumption and hardware cost of area are brought. If decoding is performed by the edge detection method, there is a problem of insufficient reliability.

In order to overcome the above problems, the present application provides a method for receiving and decoding manchester codes, comprising:

s1, receiving effective data;

s2, generating a detection clock signal according to the effective data transmission rate;

s3, detecting effective data in a detection window set on a time axis according to the detection clock signal.

Wherein the detection window only partially covers the valid data duration, and does not need to cover the entire valid data duration (i.e., all from left to right, from beginning to end), in sharp contrast to the prior art which covers the entire valid data duration. In the real case of fig. 1, the jump takes a certain period of time, but the period of time is also short, such as each small rectangle standing up, the width is narrow, and the detection of valid data can be achieved only by covering this narrow portion.

The beneficial effects of the embodiment of the application can be obtained: each set window corresponds to 1-bit effective data, so that detection of excessive and too-dense windows is avoided, detection of multiple windows and 1-bit effective data are avoided, and hardware cost is reduced. And each bit can be sampled without oversampling, so that the reliability is ensured. The embodiment of the application can ensure the signal quality of the clock and the recovered data, reduce the error rate and improve the link reliability.

The detection clock signal plays a key role, and two ways of generating the detection clock signal provided by the application are described below.

The first way to detect the generation of the clock signal is to set step S2-a before step S2:

S2-A, generating a detection clock signal with set frequency according to the effective data transmission rate stored in the register or the nonvolatile memory.

The second way to generate the detection clock signal is to set the transmitted data into the form of data header+valid data, i.e. there is a data header before valid data, and the period or frequency of the detection clock signal is obtained according to the data header by means of a preset protocol or rule. I.e. before step S2 or S1, step S1-a is set:

S1-A-1, receiving a data head, wherein the data head carries transmission rate information of effective data;

S1-A-2, analyzing the effective data transmission rate information in the data head (namely obtaining the effective data transmission rate).

Step s2 may then be performed to generate a detection clock signal based on the effective data transfer rate.

In this case, step S3 may be to detect the valid data in the set detection window after the reception of the data header on the time axis according to the detection clock signal, and obtain a detection result of 0 or 1.

In one embodiment, the data header contains a data header end identifier to characterize the end of the data header and the beginning of valid data.

In yet another embodiment, the data header employs a special coding scheme other than Manchester coding, such as a non-return to zero code, e.g., a high level for a 1 and a low level for a 0.

In one embodiment, the transmission rate information of the valid data is carried with a level duration in the data header. Fig. 2 gives several examples about data headers. In the figure, 201 (large dashed box on the left in the figure) is a data header, 202 (bits in thick dashed box in the data header) is a data header end flag, 203 (large dashed box on the right in the figure) is valid data, and thick dashed box 204 in valid data is a detection window. The up-jump is detected in the detection window, then this bit is 1; a down-jump is detected, then this bit is 0. No detection is made at times outside the detection window.

In one embodiment, the data head adopts a clock coding mode, that is, the data of the data head except the data head end mark adopts high-low level periodic alternating distribution, and the transmission rate information of the effective data is carried by using the duration time of each high level or low level.

As in fig. 2 (a), the header is 101010100, and the last bit "0" is the header end flag. The duration of either high level or low level of the data header other than the data header end flag is half of the period of transmitting the manchester code in the valid data. The period of the detection clock signal is consistent with the period of the transmission Manchester code in the effective data, and is 2 times of the duration of any high level or low level of the data except the end mark of the data head.

As in fig. 2 (b), the header is 110011000, and the last bit "0" is the header end flag. The duration of either high level or low level of the data header other than the data header end flag is the same as 1 time of the period of transmitting the manchester code in the valid data. The period of the detection clock signal is 2 times the period of transmitting Manchester codes in the effective data, and is also 2 times the duration of any one high level or low level of the data except the data head end mark of the data head.

In other embodiments, the duration of either high level or low level of the data header other than the data header end flag may also be set to be an integer or non-integer multiple of the period of transmitting manchester code in the effective data.

The end of header identification may be in other identifiable, pre-set forms that characterize the end of header and the beginning of valid data. In one embodiment, the end of header identification is also used to carry header ID information. In one embodiment, the end of header identification is also used for packet transmit and receive synchronization.

In one embodiment, the data header may also be in a non-clock encoding mode, for example, the data header is 111100001010, i.e., a high level of 4 units of time+a low level of 4 units of time+a high level of 1 units of time+a low level of 1 units of Time, then the maximum value of the high level width may be determined from the data header to be 4 units of Time, the minimum width of the low level to be 1 unit of Time, and the effective data transmission rate may be determined by a Time-to-Digital Converter (TDC) based on the minimum width of the low level, the minimum width of the high level, and the like.

In general, the data header is configured as a fixed waveform, and an effective data transmission rate can be determined based on time information in the extracted waveform.

The beneficial effects of the arrangement of the data head can be obtained: under the condition of the data head, the receiving and decoding method can adapt to data transmission at different rates, namely, the transmission of Manchester encoded data supporting variable data rates, and although the effective data transmission rates are different, the rate of the following effective data transmission can be determined according to the rate of the data head transmission, so that the data can be read according to bits, and oversampling is avoided. The data header may also have additional functionality: synchronization or frequency information can be provided in an auxiliary manner for the receiver of the Manchester code to perform frequency and phase calibration.

The transmission of the manchester encoded data with the variable data rate may be different data rates of different transmitting apparatuses or may be variable data rates of the same transmitting apparatus. The data units may be arranged as fixed length data, each data unit having a data header and valid data. It is also possible to provide that a transmitting means transmits the data header at a timing that will always be transmitted at the data rate of the previous data header before the next data header is transmitted.

In order to adapt to signals with different intensities, for example, there may be a strong signal, a large voltage difference between a high level and a low level, a weak signal, and a small voltage difference between a high level and a low level, and the voltage difference between the high level and the low level of the signal may be unified into a stable voltage difference through one amplifier. The following can be set in the reception decoding method of manchester code:

step S1-A-1 comprises determining amplification factor according to the voltage difference between high level and low level in the data head, and amplifying the signal of the data head;

and step S1, firstly amplifying the signal of the effective data according to the amplification factor, and detecting the amplified effective data signal in step S3.

Thus, detection of equal reliability can be achieved for signals of different intensities. The steps are comprehensively arranged into an implementation mode with better effect, and the implementation mode is as follows:

S1-A-1, receiving a data head, wherein the data head comprises a high level and a low level, determining amplification factors according to a voltage difference between the high level and the low level in the data head, and amplifying signals of the data head;

S1-A-2, analyzing effective data transmission rate information in the data head;

s1, receiving effective data, and amplifying signals of the effective data according to the amplification factors to obtain amplified effective data;

s2, generating a detection clock signal according to the effective data transmission rate;

s3, detecting the amplified effective data in a detection window set on a time axis according to the detection clock signal.

Based on the above embodiment, the embodiment of the application further provides a receiving and decoding device of the manchester code. The method for receiving and decoding the Manchester code of the present application can be used for a device for receiving and decoding the Manchester code. As shown in fig. 3, the manchester code receiving and decoding apparatus 300 includes:

a clock module 301, configured to generate a detection clock signal according to an effective data transmission rate;

the window detection module 302 is configured to receive the valid data, and detect the valid data according to the detection clock signal in a detection window set on a time axis; wherein the detection window only partially covers the valid data duration.

According to the embodiment of the application, the time start-stop range of the detection window can be set through setting the clock, so that the clock and the data can be simply extracted, and the hardware power consumption area cost is reduced.

In a manner corresponding to the generation of the first detection clock signal described above, as shown in fig. 4, a register or a nonvolatile memory 303 may be provided for generating the detection clock signal of a set frequency, and specific functions may be set as follows:

1. the register or nonvolatile memory 303 may store data rate information, send a data rate signal to the clock module 301, and the clock module 301 generates a detection clock signal CLKIN and sends it to the window detection module 302.

2. The register or non-volatile memory 303 may also store a definition of the detection window size, and may send a detection window size signal to the window detection module 302 to cause the detection window detection module to detect valid data at one time in the detection window or during a detection window period based on the detection window size represented by the detection window size signal.

The register or nonvolatile memory 303 may be provided inside the manchester code receiving and decoding apparatus 300 or may be provided outside the manchester code receiving and decoding apparatus 300.

In fig. 4, a data header end identifier detecting module 305 is further provided, and may be configured to detect a data header end identifier, and send a data header end signal to the clock module when the data header end identifier is detected, so that the clock module may start to operate after receiving the data header end signal, that is, may not generate the detection clock signal CLKIN before receiving the data header end signal, so that power consumption may be further reduced.

Corresponding to the manner of generating the detection clock signal according to the header parsing, as shown in fig. 5, the receiving and decoding apparatus of the manchester code may be provided to include:

the rate detection module 306 is configured to receive a data header, where the data header carries transmission rate information of valid data, and parse the valid data transmission rate information in the data header.

At this time, the window detection module 302 is configured to detect valid data in a set detection window after the data header on the time axis is received according to the detection clock signal.

For the window detection module 302, as shown in fig. 6, it may be provided that:

an amplifying module 3021, configured to determine an amplification factor according to a voltage difference between a high level and a low level in the data header, amplify a signal of the valid data, and output an amplified signal;

a generating module 3022, configured to generate a clock trigger signal CLK according to the detected clock signal CLKIN;

the D flip-flop module 3023 is configured to generate the output DATA OUT according to the clock trigger signal CLK and the amplified signal.

Since the D flip-flop module does not need to generate output data in the period of the non-detection window, the D flip-flop module only needs to operate in the period of the detection window, and the amplifying module is the same. The amplification module can be controlled to operate or not by setting the enable signal EN.

In addition, if the amplifying module does not output the latest amplifying signal when the D flip-flop receives the clock trigger signal CLK, an error may be caused. To ensure that the D flip-flop module has completed according to the latest amplified signal setting when receiving the clock trigger signal, the enable signal may be set a time Td earlier than the clock trigger signal. Specifically, it is possible to set up:

the amplifying module 3021 is configured to receive an enable signal EN, amplify the signal of the valid data under an enable condition, and output an amplified signal to the D flip-flop module 3023;

the generating module 3022 is configured to generate a clock trigger signal CLK and an enable signal EN according to the detected clock signal and the size of the detection window, where the enable signal EN is earlier than the clock trigger signal CLK, so as to ensure that when the D flip-flop module receives the clock trigger signal CLK, the setting of the enable signal according to the amplified signal is completed, and a period of a non-detection window of the enable signal in the effective data transmission process may be low level, so that the amplifying module is controlled to not work.

Since the amplifying module and the D flip-flop module do not operate when the enable signal EN is at a low level, power consumption can be further saved.

The above can be used as a setting for manchester encoding, and for differential manchester encoding, as shown in fig. 7, after a series of detection results of 0 or 1 are obtained, adjacent bits are obtained, and exclusive or operation is performed on the adjacent bits, so that final output data can be obtained.

That is, as shown in fig. 8, an XOR logic module 308 may be connected to the output end of the window detection module 302, and the output DATA OUT may be obtained by performing an XOR operation on the adjacent bits output by the window detection module 302.

In general, the application provides a method and a device for receiving and decoding Manchester codes, which can realize low hardware cost and high reliability receiving and decoding on Manchester codes and differential Manchester codes.

The above-described embodiments of the apparatus and system are merely illustrative, and some or all of the modules may be selected according to actual needs to achieve the objectives of the present embodiment. Those of ordinary skill in the art will understand and implement the present application without undue burden.

The foregoing is only a preferred embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the technical scope of the present application should be covered by the scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims (11)

1. A method for receiving and decoding manchester codes, comprising:

receiving valid data;

generating a detection clock signal according to the effective data transmission rate;

detecting effective data in a detection window set on a time axis according to the detection clock signal; wherein the detection window only partially covers the valid data duration.

2. The method of receiving and decoding manchester code according to claim 1, wherein the step of generating the detection clock signal according to the effective data transmission rate comprises:

and generating a detection clock signal with a set frequency according to the effective data transmission rate stored in the register or the nonvolatile memory.

3. The method of receiving and decoding manchester code according to claim 1, wherein before the step of generating the detection clock signal according to the effective data transmission rate, or before the step of receiving the effective data, the method further comprises:

receiving a data head, wherein the data head carries transmission rate information of effective data;

and analyzing the effective data transmission rate information in the data head.

4. A method of decoding a reception of manchester codes according to claim 3 wherein the data header contains a data header end identifier to characterize the end of the data header and the start of valid data.

5. The method for decoding and receiving Manchester code according to claim 4, wherein the data of the data header other than the data header end identifier is periodically distributed with high and low levels, and the transmission rate information of the effective data is carried by using the duration of each high level or low level.

6. The method of receiving and decoding a manchester code according to claim 3, wherein the step of receiving the data header is preceded by the step of receiving the valid data, and wherein the step of receiving the data header comprises: determining the amplification factor according to the voltage difference between the high level and the low level in the data head, and amplifying the signal of the data head;

the step of receiving valid data includes: and amplifying the signal of the effective data according to the amplification factor.

7. A receiving and decoding apparatus of manchester code, comprising:

the clock module is used for generating a detection clock signal according to the effective data transmission rate;

the window detection module is used for receiving the effective data, and detecting the effective data in a detection window set on a time axis according to the detection clock signal; wherein the detection window only partially covers the valid data duration.

8. The receiving and decoding device of manchester code according to claim 7, wherein the receiving and decoding device of manchester code further comprises:

a register or nonvolatile memory for storing an effective data transfer rate;

the clock module is used for generating a detection clock signal with a set frequency according to the effective data transmission rate stored in the register or the nonvolatile memory.

9. The receiving and decoding device of manchester code according to claim 7, wherein the receiving and decoding device of manchester code further comprises:

the rate detection module is used for receiving the data head, the data head carries the transmission rate information of the effective data, and the effective data transmission rate information in the data head is analyzed.

10. The apparatus for decoding and receiving manchester code of claim 9 wherein the window detecting means comprises:

the amplifying module is used for determining the amplification factor according to the voltage difference between the high level and the low level in the data head, amplifying the signal of the effective data and outputting an amplified signal;

the generating module is used for generating a clock trigger signal and an enabling signal according to the detection clock signal;

and the D trigger module is used for generating output data according to the clock trigger signal and the amplified signal.

11. The receiving and decoding device of manchester code according to claim 10, wherein the amplifying module is configured to receive an enable signal, amplify the signal of the valid data under an enable condition, and output the amplified signal to the D flip-flop module;

the generation module is used for generating a clock trigger signal and an enabling signal according to the detection clock signal and the size of the detection window, and the enabling signal is earlier than the clock trigger signal so as to ensure that the D trigger module is set according to the amplifying signal when receiving the clock trigger signal.