CN103905070B - Signal transmission device and method, signal receiving device and method for balance compensation - Google Patents

Abstract

The present invention discloses a signal transmission device and method, a balanced compensation signal receiving device and method, which are used to generate a transmission signal according to a pulse amplitude modulation signal. The signal transmission device includes: a filter characteristic compensation circuit, which is used to generate a compensation signal according to the pulse amplitude modulation signal and a filter function; a filter, coupled to the filter characteristic compensation circuit, which is used to filter the compensation signal according to the aforementioned filter function to generate a filtered signal; and an analog front-end circuit, which is used to generate the transmission signal according to the filtered signal.

Description

Signal transmission device and method, signal receiving device and method for balance compensation

technical field

The present invention relates to a signal transmission device and its method, and a signal receiving device and its method, in particular to a signal transmission device and its method for compensation based on filter characteristics, and a balance compensation signal receiving device and its method.

Background technique

Since electronic products generate electromagnetic radiation during operation, it may interfere with the normal operation of other devices and even affect human health. Therefore, most countries have established regulations on the electromagnetic radiation of electronic products to prevent electromagnetic interference (Electromagnetic Interference, EMI) come to harm. In some fields, the regulations on electromagnetic interference are particularly strict. For example, for a vehicle network communication device, the spectrum of the signal sent by it should be concentrated in low frequency to comply with the relevant vehicle electromagnetic interference regulations. In the current technology, a low-pass filter is used to filter the signal to be transmitted by the vehicle network communication device, so as to limit the frequency spectrum of the transmitted signal to a low-frequency range, thereby satisfying relevant regulations. However, for the vehicle network communication device, the frequency spectrum of the transmitted signal is concentrated in the low frequency, which also means the reduction of the signal transmission distance and the throughput (Throughput). The loss of becomes the problem that those skilled in the art want to solve.

Contents of the invention

In view of the above, an object of the present invention is to provide a signal transmission device and method for compensating based on filter characteristics, and a signal receiving device for balance compensation and method thereof, so as to solve the problems in the prior art.

Another object of the present invention is to provide a signal transmission device and method for compensation based on filter characteristics and a signal receiving device for balance compensation and method thereof, so as to avoid or reduce signal transmission distance and transmission distance while complying with electromagnetic interference regulations. amount of loss.

The invention discloses a signal transmission device for compensating according to filter characteristics, which is used to generate a transmission signal according to a source signal. According to an embodiment of the present invention, the signal transmission device includes: a filter characteristic compensation circuit, used to generate a compensation signal according to the source signal and a filter function; a filter, coupled to the filter characteristic compensation circuit, used to generate a compensation signal according to the source signal The filter function filters the compensation signal to generate a filter signal; and an analog front-end circuit is used to generate the transmission signal according to the filter signal.

According to an embodiment of the present invention, the aforementioned source signal is a pulse amplitude modulation signal, and the aforementioned filter characteristic compensation circuit includes: an operation circuit for generating an operation signal according to the pulse amplitude modulation signal and a feedback signal; A level adjustment circuit, coupled to the operation circuit, is used to generate the compensation signal according to the operation signal, wherein the signal level of the pulse amplitude modulation signal is between an upper signal level limit and a signal level lower limit, and the The level adjustment circuit adjusts the level of the calculation signal higher than the upper limit of the signal level or lower than the lower limit of the signal level to generate the compensation signal, so that the signal level of the compensation signal is between the upper limit and the lower limit of the signal level and a feedback circuit, coupled to the level adjustment circuit, for processing the compensation signal according to a feedback function to generate the feedback signal, and the feedback function is associated with the filter function.

According to an embodiment of the present invention, the signal level of the aforementioned pulse amplitude modulation signal corresponds to one of 2M+1 signal levels, and when the operation signal exceeds the upper limit of the signal level, the level adjustment circuit lowers the The signal level of the operation signal reaches n×(2M+1) levels to generate the compensation signal, and when the operation signal is lower than the lower limit of the signal level, the level adjustment circuit raises the signal of the operation signal The level reaches n×(2M+1) levels to generate the compensation signal, the above n and M are both positive integers, and n can vary.

The invention also discloses a signal receiving device with balance compensation, which is used for receiving a transmission signal. According to an embodiment of the present invention, the signal receiving device includes: an analog front-end circuit, used to generate a received signal according to the transmitted signal; Level adjustment of the received signal or a derivative signal of the received signal with a signal level lower limit to generate a pulse modulated signal, so that the signal level of the pulse modulated signal is between the upper limit and the lower limit of the signal level , wherein the signal level of the pulse amplitude modulation signal corresponds to one of 2M+1 signal levels, and when the received signal or derived signal exceeds the upper limit of the signal level, the level restoration circuit lowers the received signal or the signal level of the derived signal reaches n×(2M+1) levels, and when the received signal or the derived signal is lower than the lower limit of the signal level, the level recovery circuit raises the level of the received signal or the derived signal The signal level reaches n×(2M+1) levels, both n and M are positive integers, and n can be adjusted.

The invention also discloses a signal transmission method compensated according to filter characteristics, which is used to generate a transmission signal according to a source signal, and is realized by a signal transmission device compensated according to filter characteristics. According to an embodiment of the present invention, the signal transmission method includes the following steps: generating a compensation signal according to the source signal and a filter function; filtering the compensation signal according to the filter function to generate a filter signal; and according to the filter signal The transmit signal is generated.

The present invention also discloses a signal receiving method with balance compensation, which is used to receive a transmission signal, and is realized by a signal receiving device with balance compensation. According to an embodiment of the present invention, the signal receiving method includes the following steps: generating a receiving signal according to the transmitting signal; when the signal level of the receiving signal or its derivative signal is higher than a signal level upper limit, downgrading the receiving signal The signal level of the signal or the derived signal reaches n×(2M+1) levels to generate a pulse modulated signal, wherein both n and M are positive integers, and n is adjustable; and when the received signal or When the signal level of the derivative signal is lower than a signal level lower limit, the signal level of the received signal or the derivative signal is raised to n×(2M+1) levels to generate the pulse modulation signal, wherein The signal level of the pulse modulation signal is between the upper limit and the lower limit of the signal level.

Regarding the characteristics, implementation and effects of the present invention, preferred embodiments are described in detail below in conjunction with the drawings.

The device and method disclosed in the present invention can filter the signal to be transmitted according to requirements or a predetermined specification (such as an electromagnetic interference specification), so that the waveform and/or frequency spectrum of the signal conform to the specification, and at the same time correspond to the signal transmission The terminal compensates the influence caused by filtering, and correspondingly balances the influence caused by the compensation at the signal receiving terminal. Therefore, the present invention can avoid or reduce the loss of signal transmission distance and/or transmission volume under the premise of meeting the requirement or the predetermined specification.

Description of drawings

FIG. 1 is a schematic diagram of an embodiment of a signal transmission device for compensation based on filter characteristics of the present invention.

FIG. 2 is a schematic diagram of an embodiment of the filter characteristic compensation circuit shown in FIG. 1 .

FIG. 3 is a schematic diagram of an embodiment of the feedback circuit of FIG. 2 .

FIG. 4 is a schematic diagram of another embodiment of a signal transmission device for compensation based on filter characteristics of the present invention.

FIG. 5 is a schematic diagram of an embodiment of a signal receiving device for balance compensation of the present invention.

FIG. 6 is a flow chart of an embodiment of a signal transmission method for compensation based on filter characteristics of the present invention.

FIG. 7 is a flowchart of an embodiment of step S610 in FIG. 6 .

FIG. 8 is a partial flow chart of another embodiment of the signal transmission method for compensation based on filter characteristics of the present invention.

FIG. 9 is a flowchart of an embodiment of a signal receiving method for balance compensation of the present invention.

Wherein, the reference signs are explained as follows:

100 signal transmission device

110 filter characteristic compensation circuit

120 filter

130 analog front-end circuit

210 arithmetic circuit

220 level adjustment circuit

230 feedback circuit

310 delay element

320 multiplying elements

330 Addition Elements

400 signal transmission device

410 first switch

420 Digital to Analog Converter

430 second switch

440 Analog to Digital Converter

450 equalizer

460 decision circuit

500 signal receiving device

510 analog front-end circuit

520 level recovery circuit

a1, a2...ak coefficient

b1, b2...bk coefficients

S610 generating a compensation signal according to a source signal and a filter function

S620 Filter the compensation signal according to the filter function to generate a filter signal

S630 generating the transmission signal according to the filtered signal

S710 generates an operation signal according to the pulse amplitude modulation signal and a feedback signal

S720 adjusts the level of the operation signal higher than the upper limit of the signal level or lower than the lower limit of the signal level to generate the compensation signal

S730 generates the feedback signal according to the compensation signal and the filter function

S810 generates an analog training signal in a calibration mode

S820 Filter the analog training signal to generate an analog filtered training signal

S830 convert the analog filtered training signal to generate a digital filtered training signal

S840 generates an equalized signal according to the digitally filtered training signal and an error feedback signal

S850 generates the error feedback signal according to the pulse amplitude modulation signal and the equalization signal

S860 Update at least one parameter according to the adjusted at least one equalizer coefficient

S910 Generate a receiving signal according to the transmitting signal

S920 When the received signal or a derived signal is higher than a signal level upper limit, lower the signal level of the received signal or the derived signal

S930 When the received signal or the derived signal is lower than a signal level lower limit, increase the signal level of the received signal or the derived signal

detailed description

The technical terms in the following explanations refer to the customary terms in this technical field. If some terms are explained or defined in this manual, the explanations or definitions of this part of the terms shall prevail. In addition, on the premise that implementation is possible, the meaning of the relative relationship between objects or events described in this specification may include direct or indirect relationship. The so-called "indirect" means that there is still an intermediate object or physical space between objects. Or refers to the existence of intermediate events or time intervals between events. Furthermore, the following content is about the signal transmission and reception technology of the communication system, and the common technologies or principles in this field will not be described in detail if they do not involve the technical features of the present invention. In addition, the shapes, sizes, proportions, and steps of the processes in the illustrations are only illustrative, and are provided for those skilled in the art to understand the present invention, rather than limiting the implementation scope of the present invention.

In addition, each embodiment of the following description has one or more technical features respectively, but this does not mean that the inventor must implement all the technical features in any embodiment at the same time, or can only separately implement the technical features in different embodiments. Some or all of the technical features. In other words, as long as the possibility of implementation is not affected, those skilled in the art can selectively implement some or all of the technical features in any embodiment according to the disclosure of the present invention and according to their own needs or design specifications , or selectively implement a combination of some or all of the technical features in multiple embodiments, so as to increase the flexibility of the implementation of the present invention.

The disclosed content of the present invention includes a signal transmission device and its method for compensation based on filtering characteristics, and a signal receiving device and its method for balance compensation. The multiple devices and methods can be based on a specification (such as an electromagnetic interference ( Electromagnetic Interference (EMI) specification) to filter the signal to be transmitted, and correspondingly compensate the influence caused by the filtering operation at the transmitting end and balance the effect caused by the compensation at the receiving end. Please note that on the premise that implementation is possible, those skilled in the art can select equivalent elements or steps to implement the present invention based on the disclosure of the present invention, that is, the implementation of the present invention is not limited to the implementation of the present invention. Disclosed Examples. In addition, since any part or all of the components included in the signal transmission and reception device of the present invention may be known individually, therefore, without affecting the full disclosure and practicability of the device invention, The following description will omit the details of the individual elements implementing the device invention. Furthermore, the signal transmission and reception method of the present invention can be realized by the device of the present invention, and may also be realized by other signal transmission and reception devices. Therefore, without affecting the full disclosure and practicability of the method invention, The following description of the method invention will focus on the method itself rather than the details of the hardware devices.

Please refer to FIG. 1 , which is a schematic diagram of an embodiment of a signal transmission device for compensating according to filter characteristics of the present invention. This embodiment can be used in a communication device (for example, an Ethernet communication device conforming to the 10GBase-T specification), and is especially suitable for a communication device with strict specifications on the waveform and frequency spectrum of the transmission signal. As shown in FIG. 1, the signal transmission device 100 of this embodiment includes: a filter characteristic compensation circuit 110, which is used to generate a compensation signal according to a source signal and a filter function. In this embodiment, the filter characteristic compensation circuit 110 includes A Tomlinson-Harashima Precoder (THP), the source signal is a Pulse Amplitude Modulation (PAM) signal, but other hardware that can be used to implement the filter characteristic compensation circuit 110 and can be used for this The signal processed by the invention must also be adopted by the present invention; a filter 120, coupled to the filter characteristic compensation circuit 110, is used to filter the compensation signal according to the filter function to generate a filter signal. Among them, the filter function is set according to an electromagnetic interference specification (EMISpecification), so that the filtered signal has a specific waveform and/or frequency spectrum and can meet the specification; and an analog front end (AnalogFrontEnd, AFE) circuit 130, coupled to The filter 120 is used for generating the transmission signal according to the filtered signal.

Please refer to FIG. 2 , which is a schematic diagram of an embodiment of the filter characteristic compensation circuit 110 in FIG. 1 . As shown in Figure 2, the filter characteristic compensation circuit 110 includes: an operation circuit 210, which is used to generate an operation signal according to the aforementioned source signal (pulse amplitude modulation signal in this embodiment) and a feedback signal, in this embodiment , the operation circuit 210 includes a subtractor (not shown), which is used to subtract the feedback signal from the pulse amplitude modulation signal to generate the operation signal. However, those skilled in the art can rely on the disclosure and Depending on requirements or specifications, a circuit with other computing effects is selected; a level adjustment circuit 220, coupled to the computing circuit 210, is used to generate the compensation signal according to the computing signal, wherein the signal level of the pulse amplitude modulation signal is at Between an upper limit of signal level and a lower limit of signal level, and the level adjustment circuit 220 adjusts the level of the calculation signal higher than the upper limit of signal level or lower than the lower limit of signal level to generate the compensation signal , so that the signal level of the compensation signal is between the upper limit and the lower limit of the signal level, more precisely, the signal level of the pulse amplitude modulation signal corresponds to 2M+1 (M is a positive integer, such as 2) signals One of the levels, when the operation signal exceeds the upper limit of the signal level, the level adjustment circuit 220 lowers the signal level of the operation signal to n×(2M+1) (n is a positive integer and can be changed, For example, 1) level to generate the compensation signal, and when the operation signal is lower than the lower limit of the signal level, the level adjustment circuit 220 raises the signal level of the operation signal to n×(2M+1) levels Level to generate the compensation signal, in this embodiment, the level adjustment circuit 220 is a modulus operation (ModulusOperation) circuit, but other circuits that can realize the above-mentioned level adjustment function also have to be adopted by the present invention; and a The feedback circuit 230, coupled to the level adjustment circuit 220, is used to generate the feedback signal according to the compensation signal. The feedback circuit 230 corresponds to a feedback function, and the feedback function is associated with the filter function. In this embodiment, the feedback function It is equal to the filter function minus 1. Under the assumption that the operation signal is equivalent to the compensation signal, the relationship between the two functions can be derived as follows:

S(D)×[1/E(D)]=S(D)-F(D){S(D)×[1/E(D)]}

∴F(D)=E(D)-1

Among them, S(D) represents the pulse amplitude modulation signal; E(D) represents the filter function (that is, 1/E(D) represents the function corresponding to the filter characteristic compensation circuit); S(D)×[1/E(D )] represents the output signal of the filter characteristic compensation circuit; F(D) represents the feedback function; and F(D){S(D)×[1/E(D)]} represents the feedback signal. However, although the above-mentioned functional relationship is adopted in the present embodiment, those skilled in the art can adjust the feedback circuit 230 according to the disclosure of the present invention and according to requirements or specifications to realize other functional relationships.

As mentioned above, an embodiment of the feedback circuit 230, as shown in FIG. 3 , includes a plurality of delay elements 310, a plurality of multiplication elements 320, and a plurality of addition elements 330, wherein each multiplication element 320 multiplies the received signal After outputting a coefficient, multiple coefficients (a1, a2...ak-1, ak and b1, b2...bk-1, bk, wherein k is a positive integer) determine the feedback function of the feedback circuit 230, further , the feedback function can be associated with the aforementioned filter function by adjusting multiple coefficients. In practice, since the filter function can be determined by the designer according to requirements or specifications, multiple coefficients can also be determined by the designer based on the filter function. In this embodiment, the feedback function can be represented by the following formula:

F(D)=E(D)-1=(b1D+b2D2+…+bkDk)/(1-a1D-a2D2-…-akDk)

Where D represents a signal passing through one delay element, D2 represents a signal passing through two delay elements, and Dk represents a signal passing through k delay elements.

Please continue to refer to FIG. 2 , in this embodiment, the feedback function is only related to the filter function, and other effects that affect the transmitted signal (such as a channel effect) can be compensated by the equalizer at the receiving end of the transmitted signal. However, in another embodiment of the present invention, the feedback function can be further related to a channel estimation function (or other functions that affect the transmitted signal), and the channel estimation function represents the influence of a channel effect on the transmitted signal , at this time, the filter characteristic compensation circuit 110 compensates the filter characteristic of the filter 120 and the influence of the channel effect according to the feedback function to generate the compensation signal. More precisely, at this time, the feedback function is equal to the filter function and the channel estimate Subtract 1 from the composite function of the measured function.

Please refer to FIG. 1 again, this embodiment may further include: a digital-to-analog converter (for example, the digital-to-analog converter 420 in FIG. 4 ), coupled to the filter characteristic compensation circuit 110, for digital-to-analog conversion of the compensation signal. analog conversion, and output the converted compensation signal to the filter 120 for subsequent processing, and the filter 120 is an analog filter at this time. However, since the analog filter may be affected by certain factors (such as process drift, temperature change, etc.) to generate characteristic deviation, the present invention further proposes a design to correct the characteristic deviation. Please refer to FIG. 4 , which is a schematic diagram of another embodiment of a signal transmission device that compensates based on filter characteristics according to the present invention. As shown in FIG. 4 , the signal transmission device 400 of this embodiment, in addition to the components shown in FIG. 1 , It further includes: a first switch 410, used to electrically connect the source signal with the filter characteristic compensation circuit 110 in a normal mode, and connect the source signal with a digital-to-analog converter in a calibration mode 420 are electrically connected together; a digital-to-analog converter 420, coupled to the filter characteristic compensation circuit 110, is used to convert the compensation signal from digital to analog in a normal mode, and output the converted compensation signal to The filter 120 is used for subsequent processing as described in the embodiment of FIG. 1. In addition, in the correction mode, the digital-to-analog converter 420 receives the source signal through the first switch 410 and converts it into an analog The training signal is output to the filter 120, and the filter 120 generates an analog filter training signal according to the analog training signal; a second switch 430 is used to electrically connect the filter 120 to the analog front-end circuit 130 in the normal mode Connected together, and in the correction mode, the filter 120 is electrically connected with an analog-to-digital converter 440; the analog-to-digital converter 440 is used to train the analog filter in the correction mode The signal is converted into a digital filter training signal; an equalizer 450 is used to generate an equalized signal according to the digital filter training signal and an error feedback signal in the correction mode, the equalizer 450 includes at least one equalizer coefficient, the equalizer The coefficient of the equalizer is adjusted according to the error feedback signal; and a decision circuit 460 is coupled to the equalizer 450 in the correction mode and coupled to the source signal through the first switch 410 for use in accordance with a preset algorithm (for example A least mean square algorithm, a normalized least mean square algorithm or a regression least square algorithm) use the source signal and the equalizer signal to generate the error feedback signal, and update the equalizer coefficient according to the adjusted At least one parameter of the filter characteristic compensation circuit 110 (such as the coefficient of the feedback circuit 230 in FIG. 3 ) is used to compensate the characteristic deviation of the filter 120. In this embodiment, the decision circuit 460 is also coupled to the first and second Two switches 410, 430 (not shown), to control the two switches 410, 430 to switch from the calibration mode to the normal mode when the calibration is completed, or to control the two switches 410, 430 to switch from the normal mode when calibration is required to that calibration mode. Please note that the above correction process can also be regarded as associating the parameters of the filter characteristic compensation circuit 110 with the filter function of the filter 120, that is, even if the parameters of the filter characteristic compensation circuit 110 cannot be determined in advance according to the filter function, they can also be determined through the filter function. The correction process is associated with this filter function.

Based on the above, in this embodiment, the equalizer 450 may include: a feedforward equalizer for generating a feedforward equalization signal according to the digitally filtered training signal and the error feedback signal, the feedforward equalizer includes at least A feed-forward equalizer coefficient, the feed-forward equalizer coefficient is adjusted according to the error feedback signal, so that the equalization effect of the feed-forward equalizer can be represented by a feed-forward equalization function A(D); and a feedback equalizer, coupled to The feedforward equalizer is used to generate the equalized signal according to the feedforward equalization signal and the error feedback signal, the feedback equalizer includes at least one feedback equalizer coefficient, and the feedback equalizer coefficient is adjusted according to the error feedback signal, so that The equalization effect of the feedback equalizer can be represented by a feedback equalizer function B(D), wherein the at least one feedforward equalizer coefficient and the at least one feedback equalizer coefficient constitute the equalizer coefficient, and the feedforward equalizer function A(D) Dividing by the feedback equalization function B(D) is equal to the aforementioned filter function E(D).

Please note that the filter 120 can also be implemented as a digital filter in addition to the aforementioned analog filter. For example, the analog front-end circuit 130 of FIG. 1 can include: a digital-to-analog converter (not shown), The filter 120 is coupled to convert the filtered signal from digital to analog. The analog front-end circuit 130 generates the transmission signal according to the converted filtered signal, and the filter 120 is a digital filter.

On the other hand, as shown in FIG. 5 , the present invention also discloses a balance compensation signal receiving device 500 for receiving the transmission signal output by the signal transmission device in FIG. 1 or FIG. 4 . The signal receiving device 500 includes: an analog front-end circuit 510, used to generate a received signal according to a transmitted signal; Adjust the level of the received signal or a derivative signal of the received signal to generate a pulse modulated signal, so that the signal level of the pulse modulated signal is between the upper limit and the lower limit of the signal level, wherein the pulse amplitude The signal level of the modulated signal corresponds to one of 2M+1 (M is a positive integer, such as 2) signal levels. When the received signal or derived signal exceeds the upper limit of the signal level, the level restoration circuit 520 Downgrade the signal level of the received signal or derived signal by n×(2M+1) (n is a positive integer and can be changed, such as 1) levels, and when the received signal or derived signal is lower than the signal level At the lower limit, the level recovery circuit 520 increases the signal level of the received signal or the derived signal by n×(2M+1) levels. In this embodiment, the level restoring circuit 520 is an analog-to-digital processing circuit, but other circuits capable of performing the above-mentioned level adjustment can also be used in the present invention. In addition, this embodiment may further include: a channel equalizer (not shown), coupled to the analog front-end circuit 510, used to generate the derivative signal according to the received signal, so as to compensate the influence of a channel effect on the transmitted signal, because The channel equalizer alone belongs to common knowledge in the technical field, so its detailed description is omitted here.

In addition to the foregoing device embodiments, the present invention also proposes a signal transmission method for compensation based on filter characteristics, which can be realized by the signal transmission device in Figure 1 or Figure 4, or by other devices capable of performing the method . As shown in Figure 6, an embodiment of the signal transmission method includes the following steps:

Step S610: Generate a compensation signal according to a source signal and a filter function;

Step S620: Filter the compensation signal according to the filter function to generate a filter signal; and

Step S630: Generate the transmission signal according to the filtered signal.

In this embodiment, the above-mentioned source signal is a pulse amplitude modulation signal, the signal level of which is between an upper signal level limit and a signal level lower limit, and step S610 may include the following steps (as shown in FIG. 7 ):

Step S710: generating an operation signal according to the pulse amplitude modulation signal and a feedback signal;

Step S720: Adjust the level of the operation signal that is higher than the upper limit of the signal level or lower than the lower limit of the signal level to generate the compensation signal, so that the signal level of the compensation signal is between the upper limit and the lower limit of the signal level between. More precisely, the signal level of the pulse amplitude modulation signal corresponds to one of 2M+1 (the M is a positive integer, such as 2) signal levels. When the operation signal exceeds the upper limit of the signal level, In this step, the signal level of the operation signal is lowered to n×(2M+1) (the n is a positive integer, such as 1) levels to generate the compensation signal, and when the operation signal is lower than the signal level Within a time limit, this step increases the signal level of the operation signal to n×(2M+1) levels to generate the compensation signal; and

Step S730: Generate the feedback signal according to the compensation signal and the filter function.

In addition, in order to correspond to the embodiment shown in FIG. 4, the signal transmission method of the present invention may further include the following steps in addition to the steps in FIG. 6 (as shown in FIG. 8):

Step S810: performing a digital-to-analog conversion on the pulse amplitude modulated signal in a calibration mode to generate an analog training signal;

Step S820: In the calibration mode, filter the analog training signal to generate an analog filtered training signal;

Step S830: performing an analog-to-digital conversion on the analog filtered training signal in the calibration mode to generate a digital filtered training signal;

Step S840: In the calibration mode, an equalized signal is generated according to the digitally filtered training signal and an error feedback signal, the equalized signal is associated with at least one equalizer coefficient, and the equalizer coefficient is adjusted according to the error feedback signal;

Step S850: generating the error feedback signal according to the PWM signal and the equalization signal in the calibration mode; and

Step S860: In the calibration mode, update at least one parameter according to the adjusted at least one equalizer coefficient, and the at least one parameter is used as a basis for generating the compensation signal in step S610.

Please note that those skilled in the art can fully understand the method embodiments in FIGS. 6 to 8 by referring to FIGS. 1 to 4 and their related descriptions. In the case of practicability, repetitive and unnecessary explanations are omitted here.

In addition, the present invention also proposes a signal receiving method with balance compensation for receiving a transmission signal. An embodiment of the signal receiving method can be realized by the signal receiving device 500 shown in FIG. 5, including the following steps (as shown in FIG. 9):

Step S910: Generate a receiving signal according to a transmitting signal;

Step S920: When the received signal or a derivative signal of the received signal is higher than a signal level upper limit, lower the signal level of the received signal or its derivative signal by n×(2M+1) levels, so as to generating a pulse modulation signal, wherein n and M are both positive integers, and n is adjustable; and

Step S930: When the received signal or its derivative signal is lower than a signal level lower limit, increase the signal level of the received signal or its derivative signal by n×(2M+1) levels to generate the pulse modulation Modulated signal, wherein the signal level of the pulse modulated signal is between the upper limit and the lower limit of the signal level.

Similarly, because those skilled in the art can refer to FIG. 5 and its related descriptions to fully understand the method embodiment of FIG. The rest of the description will be omitted. However, please note that unless the steps in FIG. 6 to FIG. 9 have an explicit order, there is no limitation on the execution order.

To sum up, the device and method disclosed in the present invention can filter the signal to be transmitted according to the requirement or a predetermined specification (such as an electromagnetic interference specification), so that the waveform and/or spectrum of the signal conform to the specification, and at the same time Correspondingly, the signal transmitting end compensates the influence caused by filtering, and correspondingly, the signal receiving end balances the effect caused by the compensation. Therefore, the present invention can avoid or reduce the loss of signal transmission distance and/or transmission volume under the premise of meeting the requirement or the predetermined specification.

Although the embodiments of the present invention are as described above, the multiple embodiments are not intended to limit the present invention, and those skilled in the art can make changes to the technical features of the present invention according to the explicit or implicit contents of the present invention. , All these changes may belong to the scope of patent protection sought by the present invention. In other words, the scope of patent protection of the present invention shall be subject to what is defined in the claims of this specification.

Claims (24)

1. A signal transmission device for compensation based on filter characteristics, used to generate a transmission signal according to a source signal, comprising: A filter characteristic compensation circuit, used to generate a compensation signal according to the source signal and a filter function; a filter, coupled to the filter characteristic compensation circuit, for filtering the compensation signal according to the filter function to generate a filter signal; and An analog front-end circuit is used for generating the transmission signal according to the filtered signal. 2. The signal transmission device for compensation based on filter characteristics as claimed in claim 1, wherein the filter characteristic compensation circuit comprises a Tomlinson-Original Channel precoder. 3. The signal transmission device for compensating according to filter characteristics as claimed in claim 1, wherein the source signal is a pulse amplitude modulated signal, and the filter characteristic compensation circuit comprises: An operation circuit, used to generate an operation signal according to the pulse amplitude modulation signal and a feedback signal; A level adjustment circuit, coupled to the operation circuit, is used to generate the compensation signal according to the operation signal, wherein the signal level of the pulse amplitude modulation signal is between an upper signal level limit and a signal level lower limit, and The level adjustment circuit adjusts the level of the calculation signal higher than the upper limit of the signal level or lower than the lower limit of the signal level to generate the compensation signal, so that the signal level of the compensation signal is between the upper limit and the upper limit of the signal level. between the lower bounds; and A feedback circuit, coupled to the level adjustment circuit, is used to process the compensation signal according to a feedback function to generate the feedback signal, and the feedback function is associated with the filter function. 4. The signal transmission device for compensation according to filter characteristics as claimed in claim 3, wherein the operation circuit subtracts the feedback signal from the pulse amplitude modulation signal to generate the operation signal. 5. The signal transmission device for compensation based on filter characteristics as claimed in claim 3, wherein the level adjustment circuit is an analog-to-digital processing circuit. 6. The signal transmission device for compensating according to filter characteristics as claimed in claim 3, wherein the signal level of the pulse amplitude modulation signal corresponds to one of 2M+1 signal levels, when the signal level of the operation signal is When the level exceeds the upper limit of the signal level, the level adjustment circuit lowers the signal level of the operation signal to n×(2M+1) levels to generate the compensation signal, and when the signal level of the operation signal is low When the signal level is at the lower limit, the level adjustment circuit raises the signal level of the operation signal to n×(2M+1) levels to generate the compensation signal, n and M are both positive integers, and n can be adjusted . 7. The signal transmission device for compensation based on filter characteristics as claimed in claim 3, wherein the feedback function is equal to the filter function minus 1. 8. The signal transmission device compensated according to filter characteristics as claimed in claim 3, wherein the feedback circuit comprises a plurality of delay elements, a plurality of multiplication elements and a plurality of addition elements, wherein each of the multiplication elements receives the received The signal is multiplied by a coefficient to output. The multiple coefficients determine the feedback function of the feedback circuit. By adjusting the multiple coefficients, the feedback function is related to the filter function. 9. The signal transmission device for compensating according to filter characteristics as claimed in claim 3, wherein the feedback function is further associated with a channel estimation function, the channel estimation function represents the influence of a channel effect on the transmitted signal, and the filter The characteristic compensation circuit compensates the filter characteristic of the filter and the influence of the channel effect through the feedback function to generate the compensation signal. 10. The signal transmission device for compensation based on filter characteristics as claimed in claim 9, wherein the feedback function is equal to a synthesis function of the filter function and the channel estimation function minus 1. 11. The signal transmission device for compensating according to filter characteristics as claimed in claim 1, further comprising: a digital-to-analog converter, coupled to the filter characteristic compensation circuit, for digital-to-analog conversion of the compensation signal, and outputting the converted compensation signal to the filter, Wherein the filter is an analog filter. 12. The signal transmission device for compensation based on filter characteristics as claimed in claim 11, further comprising: a first switch for electrically connecting the source signal with the filter characteristic compensation circuit in a normal mode, and electrically connecting the source signal with the digital-to-analog converter in a calibration mode , wherein the digital-to-analog converter converts the source signal into an analog training signal and outputs it to the filter in the calibration mode, and the filter generates an analog filtered training signal according to the analog training signal; a second switch for electrically connecting the filter with the analog front-end circuit in the normal mode, and electrically connecting the filter with an analog-to-digital converter in the calibration mode; the analog-to-digital converter for converting the analog filtered training signal into a digital filtered training signal in the calibration mode; An equalizer, coupled to the analog-to-digital converter, is used to generate an equalized signal according to the digitally filtered training signal and an error feedback signal in the calibration mode, the equalizer includes at least one equalizer coefficient, and the at least one equalizer The coefficients of the detector are adjusted according to the error feedback signal; and a decision circuit, coupled to the equalizer and coupled to the source signal via the first switch in the calibration mode, for generating the error feedback signal according to the source signal and the equalized signal in the calibration mode, and adjusting The at least one equalizer coefficient is used to update at least one parameter of the filter characteristic compensation circuit, so as to correct the characteristic deviation of the filter. 13. The signal transmission device for compensation based on filter characteristics as claimed in claim 12, the decision circuit is also coupled to the first switch and the second switch to control the first switch and the second switch when the calibration is completed Switch from the calibration mode back to the normal mode, or control the two switches to switch from the normal mode to the calibration mode when calibration is required. 14. The signal transmission device for compensating according to filter characteristics as claimed in claim 12, wherein the equalizer comprises: A feed-forward equalizer, used to generate a feed-forward equalization signal according to the digitally filtered training signal and the error feedback signal, the feed-forward equalizer includes at least one feed-forward equalizer coefficient, and the at least one feed-forward equalizer coefficient is based on the The error feedback signal is adjusted; and A feedback equalizer, coupled to the feedforward equalizer, is used to generate the equalized signal according to the feedforward equalizer signal and the error feedback signal, the feedback equalizer includes at least one feedback equalizer coefficient, and the at least one feedback equalizer coefficient Adjust according to the error feedback signal, Wherein the at least one feed-forward equalizer coefficient and the at least one feedback equalizer coefficient constitute the equalizer coefficient. 15. The signal transmission device for compensation based on filter characteristics as claimed in claim 14, wherein the equalization effect of the feedforward equalizer is represented by a feedforward equalization function, and the equalization effect of the feedback equalizer is represented by a feedback equalization function, And the feed-forward equalization function divided by the feedback equalization function is equal to the filter function. 16. The signal transmission device for compensation based on filter characteristics as claimed in claim 1, wherein the analog front-end circuit comprises: a digital-to-analog converter coupled to the filter for digital-to-analog conversion of the filtered signal, the analog front-end circuit generates the transmission signal according to the converted filtered signal, Wherein the filter is a digital filter. 17. A signal receiving device for balance compensation, used to receive a transmission signal, comprising: an analog front-end circuit for generating a received signal according to the transmitted signal; and A level recovery circuit, used to adjust the level of the received signal or a derivative signal of the received signal that is higher than a signal level upper limit or lower than a signal level lower limit, so as to generate a pulse modulation signal, so that The signal level of the pulse modulation signal is between the upper limit and the lower limit of the signal level, The signal level of the pulse modulation signal corresponds to one of the 2M+1 signal levels. When the signal level of the received signal or the derivative signal is higher than the upper limit of the signal level, the level returns to the circuit modulation Decrease the signal level of the received signal or the derived signal by n×(2M+1) levels, and when the signal level of the received signal or the derived signal is lower than the lower limit of the signal level, the level is restored The circuit raises the signal level of the received signal or the derivative signal to n×(2M+1) levels, where n and M are both positive integers, and n can be adjusted. 18. The signal receiving device with balance compensation as claimed in claim 17, wherein the level restoring circuit is an analog-to-digital processing circuit. 19. The signal receiving device for balance compensation as claimed in claim 17, further comprising: A channel equalizer is used to compensate the influence of a channel effect on the transmitted signal, thereby generating the derivative signal according to the received signal. 20. A signal transmission method compensated according to filter characteristics, used for generating a transmission signal according to a source signal, realized by a signal transmission device compensated according to filter characteristics, comprising the following steps: generating a compensation signal according to the source signal and a filter function; filtering the compensation signal according to the filter function to generate a filtered signal; and The transmission signal is generated according to the filtered signal. 21. The signal transmission method for compensation based on filter characteristics as claimed in claim 20, wherein the source signal is a pulse amplitude modulation signal, and the signal level of the pulse amplitude modulation signal is at a signal level upper limit and a signal level Between the lower limit of the level, and the steps of generating the compensation signal include: generating an operation signal according to the pulse amplitude modulation signal and a feedback signal; adjusting the level of the operation signal that is higher than the upper limit of the signal level or lower than the lower limit of the signal level to generate the compensation signal, so that the signal level of the compensation signal is between the upper limit and the lower limit of the signal level; and The feedback signal is generated according to the compensation signal and the filter function. 22. The signal transmission method for compensation based on filter characteristics as claimed in claim 21, wherein the signal level of the pulse amplitude modulation signal corresponds to one of 2M+1 signal levels, and the step of generating the compensation signal Include: When the operation signal exceeds the upper limit of the signal level, downgrade the signal level of the operation signal by n×(2M+1) levels to generate the compensation signal; and When the operation signal is lower than the lower limit of the signal level, the signal level of the operation signal is raised to n×(2M+1) levels to generate the compensation signal, Where n and M are both positive integers, and n can be adjusted. 23. The signal transmission method for compensation based on filter characteristics as claimed in claim 20, further comprising: performing a digital-to-analog conversion on the source signal in a calibration mode to generate an analog training signal; In the calibration mode, filtering the analog training signal to generate an analog filtered training signal; performing an analog-to-digital conversion on the analog filtered training signal in the calibration mode to generate a digital filtered training signal; In the correction mode, an equalized signal is generated according to the digitally filtered training signal and an error feedback signal, the equalized signal is associated with at least one equalizer coefficient, and the at least one equalizer coefficient is adjusted according to the error feedback signal; generating the error feedback signal according to the source signal and the equalized signal in the correction mode; and In the correction mode, at least one parameter is updated according to the adjusted at least one equalizer coefficient, and the at least one parameter is used as a basis for generating the compensation signal. 24. A signal receiving method with balance compensation, which is used to receive a transmission signal, and is realized by a signal receiving device with balance compensation, comprising the following steps: generating a receiving signal according to the transmitting signal; downgrading the signal level of the received signal or a derivative signal of the received signal by n×(2M+1) levels when the signal level of the received signal or a derivative signal of the received signal is higher than an upper signal level limit, to generate a pulse modulation signal, wherein n and M are both positive integers, and n is adjustable; and When the signal level of the received signal or the derived signal is lower than a signal level lower limit, raising the signal level of the received signal or the derived signal by n×(2M+1) levels to generate the pulse modulation signal, Wherein the signal level of the pulse modulation signal is between the upper limit and the lower limit of the signal level.