TW201301890A - Signal transmitting apparatus and transmitter and receiver thereof - Google Patents

Abstract

A signal transmitting apparatus comprises a transmitter and a receiver. The transmitter filters a pair of digital differential signals received from an image source according to a first passing frequency range to output a pair of filtered digital differential signals, and converts a single-ended audio signal into a pair of differential audio signal, thereby filtering the pair of differential audio signal according to a second passing frequency range to output a pair of filtered differential audio signals. The pair of filtered digital differential signals and the pair of filtered differential audio signals are synthesized into a pair of synthesized differential signals. The receiver receives the pair of synthesized differential signals from a pair of differential transmission cables, and filters the pair of synthesized differential signals according to first passing frequency range and second passing frequency range respectively to revert pair of digital differential signals and the pair of differential audio signals, thereby converting the pair of differential audio signals into the single-ended audio signal.

Description

Signal transmission device and its transmitter and receiver

The present invention relates to signal transmission, and more particularly to a signal transmission device and its transmitter and receiver, which can synthesize sound and video signals through filters having different frequencies without additional processing or decoding components. Does not interfere with each other.

In recent years, multimedia audio and video technology has developed quite rapidly. For example, a high-definition multimedia interface (HDMI) or a digital video interface (DVI) that can transmit sound and video together, because it transmits uncompressed audio through the same cable. The signal and the high-resolution video signal do not need to convert analog signals into digital signals (A/D) or digital signals into analog signals (D/A), so the target of distortion-free output can be achieved.

Taking the HDMI video signal as an example, suppose the cable extension of the high-resolution multimedia interface is CAT-5 or CAT-6 twisted pair cable (category 5 or category 6 cable), if it is minimized by 1080P. For example, the transition signal (TMDS) is a differential signal (TMDS). Since the 1080P system has 1080 horizontal scanning lines in the vertical direction of the picture, the resolution of the picture is 1920×1080, so the bandwidth required for transmission is higher. Large, about 1.65Gbps. Therefore, when the minimum transmission differential signal of the frequency of 1650MHz is transmitted through the CAT-5 twisted pair, it can only transmit about 40 meters away, once the transmission distance between the audio and video input end of the high resolution multimedia interface and the audio and video output end For a long time, the signal extender disposed between the video input and the audio output usually requires a repeater design.

Since the HDMI signal feature cannot transmit a long distance under high-definition video output, and the HDMI dedicated signal line is quite expensive, how to use a relatively inexpensive wire for long-distance HDMI signal transmission becomes The problem that needs to be overcome. Traditionally, since a CAT-5 or CAT-6 network route contains only four pairs of differential transmission lines, the DVI or HDMI video signal (TMDS) itself needs to be transmitted through four pairs of differential transmission lines, and digital audio signals ( For example, SPDIF) and/or analog audio signals are also required to be carried on the four pairs of differential transmission lines. Therefore, in order to achieve the goal of setting a CAT-5 network route only between the transmitter and receiver of the signal extender, most of them are generally Additional processing of signal processing or decoding components, such as DSP, MCU, FPGA, or encoder/decoder, for signal processing of TMDS video signals, digital audio signals, and/or analog audio signals, to digital audio signals and / or analog signal is contained in the TMDS video signal.

However, the above method not only easily causes interference between the TMDS video signal and the audio signal, but also requires more hardware cost and longer signal processing time, which seriously weakens the market competitiveness of the signal extender.

Accordingly, the present invention is directed to a signal transmission apparatus and its transmitter and receiver to solve the above-mentioned problems encountered in the prior art.

One aspect of the invention is to propose a signal transmission device. In one embodiment, the signal transmission device includes a transmitter, a pair of differential transmission lines, and a receiver. The transmitter includes a single-ended/differential signal conversion module and a first filter module and a second filter module having different passbands. The input end of the second filter module is coupled to the single-ended/differential signal conversion module, and the output end of the second filter module is coupled to the output end of the first filter module. The first filter module filters the pair of digital differential signals received from the image source according to the first pass frequency band to output a pair of filtered digital differential signals. The single-ended/differential signal conversion module converts the single-ended audio signal into a pair of differential audio signals, and the second filter module filters the pair of differential audio signals according to the second passband to output a pair of differential signals. Sound signal. The pair of filtered digital differential signals and the pair of filtered differential audio signals are combined into a pair of combined differential signals. The pair of differential transmission lines are coupled to the transmitter for transmitting the pair of synthesized differential signals.

The receiver receives the pair of synthesized differential signals from the pair of differential transmission lines, and the receiver includes a third filter module, a fourth filter module, and a differential/single-ended signal conversion module. The input end of the third filter module is coupled to the input end of the fourth filter module, and the differential/single-ended signal conversion module is coupled to the output end of the fourth filter module. The third filter module filters the pair of synthesized differential signals according to the first pass frequency band to output the logarithmic differential signal. The fourth filter module filters the pair of composite differential signals according to the second passband to output the pair of differential voice signals, and converts the differential voice signals into single-ended signals by the differential/single-ended signal conversion module. Sound signal.

In another embodiment, the signal transmission device includes a transmitter, a complex pair of differential transmission lines, and a receiver. The transmitter includes a first filter module, a single-ended/differential signal conversion module, and a second filter module. The first filter module includes a plurality of high-pass filter units for high-pass filtering the complex logarithmic differential signals received from the image source to output a complex pair of high-pass filtered digital differential signals. The single-ended/differential signal conversion module is configured to convert at least one single-ended audio signal into at least one pair of differential audio signals. The second filter module includes at least one low-pass filter unit, and the input end is coupled to the single-ended/differential signal conversion module and the output end thereof is coupled to the output end of the first filter module. The at least one low pass filtering unit performs low pass filtering on the at least one pair of differential audio signals to output at least one pair of low pass filtered differential audio signals, such that the at least one pair of low pass filtered differential audio signals are synthesized to the complex pair The high pass filters at least one pair of high pass filtered digital differential signals of the digital differential signals to form a complex pair of synthesized differential signals. The complex pair of differential transmission lines are coupled to the transmitter for transmitting the complex pair of synthesized differential signals.

The receiver includes a third filter module, a fourth filter module, and a differential/single-ended signal conversion module. The third filter module includes the plurality of high-pass filter units for performing high-pass filtering on the complex-pair composite differential signals to restore the complex logarithmic differential signals, and outputting the signals to the image display device. The fourth filter module includes the at least one low-pass filter unit, and the input end is coupled to the input end of the third filter module. The at least one low pass filtering unit low pass filters the complex pair of synthesized differential signals to restore the at least one pair of differential audio signals. The differential/single-ended signal conversion module is coupled to the output end of the fourth filter module for converting the at least one pair of differential audio signals into the at least one single-ended audio signal.

Another aspect of the invention is to propose a conveyor. In one embodiment, the transmitter is applied to a signal transmission device. The transmitter includes a single-ended/differential signal conversion module and a first filter module and a second filter module having different passbands. The input end of the second filter module is coupled to the single-ended/differential signal conversion module, and the output end of the second filter module is coupled to the output end of the first filter module. The first filter module filters the pair of digital differential signals received from the image source according to the first pass frequency band to output a pair of filtered digital differential signals. The single-ended/differential signal conversion module converts the single-ended audio signal into a pair of differential audio signals, and the second filter module filters the pair of differential audio signals according to the second passband to output a pair of differential signals. Sound signal. The pair of filtered digital differential signals and the pair of filtered differential audio signals are combined into a pair of combined differential signals.

In another embodiment, the transmitter includes a first filter module, a single-ended/differential signal conversion module, and a second filter module. The first filter module includes a plurality of high-pass filter units for high-pass filtering the complex logarithmic differential signals received from the image source to output a complex pair of high-pass filtered digital differential signals. The single-ended/differential signal conversion module is configured to convert at least one single-ended audio signal into at least one pair of differential audio signals. The second filter module includes at least one low-pass filter unit, and the input end is coupled to the single-ended/differential signal conversion module and the output end thereof is coupled to the output end of the first filter module. The at least one low pass filtering unit performs low pass filtering on the at least one pair of differential audio signals to output at least one pair of low pass filtered differential audio signals, such that the at least one pair of low pass filtered differential audio signals are synthesized to the complex pair The high pass filters at least one pair of high pass filtered digital differential signals of the digital differential signals to form a complex pair of synthesized differential signals.

Another aspect of the invention is to propose a receiver. In one embodiment, the receiver is applied to a signal transmission device. The receiver is configured to receive a pair of synthesized differential signals, and the pair of synthesized differential signals are synthesized by a pair of digital differential signals and a pair of differential voice signals. The receiver includes a first filter module, a second filter module, and a differential/single-ended signal conversion module. The input end of the first filter module is coupled to the input end of the second filter module, and the differential/single-ended signal conversion module is coupled to the output end of the second filter module. The first filter module filters the pair of synthesized differential signals according to the first pass frequency band to output the logarithmic differential signal. The second filter module filters the pair of combined differential signals according to the second passband to output the pair of differential voice signals, and converts the pair of differential voice signals into single-ended by the differential/single-ended signal conversion module. Sound signal.

In another embodiment, the receiver includes a first filter module, a second filter module, and a differential/single-ended signal conversion module. The first filter module includes a plurality of high-pass filter units for performing high-pass filtering on the complex-pair composite differential signals to restore the complex logarithmic differential signals, and outputting the signals to the image display device. The second filter module includes at least one low-pass filter unit, and an input end thereof is coupled to the input end of the first filter module. The at least one low pass filtering unit performs low pass filtering on the complex pair of synthesized differential signals to restore the at least one pair of differential audio signals. The differential/single-ended signal conversion module is coupled to the output end of the second filter module for converting the at least one pair of differential audio signals into at least one single-ended audio signal.

The advantages and spirit of the present invention will be further understood from the following detailed description of the invention.

A preferred embodiment of the present invention is a signal transmission device. In fact, the signal transmission device can be an audio/video extender or a video switcher, and is applied to a high-resolution multimedia interface capable of integrating sound and video transmission together or a keyboard-mouse-monitor switcher (KVM switch). , but not limited to this. Since the high-resolution multimedia interface transmits uncompressed audio signals and high-resolution video signals through the same network route, analog signals are not converted into digital signals (A/D) or digital signals are converted into analog signals (D). /A) program, so the goal of distortion-free output can be achieved.

Please refer to FIG. 1 , which is a schematic diagram of a signal transmission device in this embodiment. As shown in FIG. 1 , the signal transmission device 2 is coupled between the first electronic device 1 and the second electronic device 3 . The first electronic device 1 is a video output device with a high-resolution multimedia interface, such as a Blu-ray DVD player or a computer or server with a digital image HDMI or DVI output, but not limited thereto; The device 3 is an audio-visual display device including a high-resolution multimedia interface, such as a digital TV with high image quality, a home theater audio-visual device, or a projection display device, but is not limited thereto.

In addition, the digital video signal and the audio signal received by the signal transmission device 2 may be from the same first electronic device 1 or from different first electronic devices 1, that is, the image source and the sound source may be the same first electronic device 1 Or different first electronic devices 1, there is no particular limitation. Similarly, the signal transmission device 2 can also output the digital video signal and the audio signal to the same second electronic device 3 or different second electronic devices 3.

In the embodiment of FIG. 1, the signal transmission device 2 includes a transmitter 20, a transmission line 21, and a receiver 22. The transmitter 20 is coupled to the first electronic device 1; the receiver 22 is coupled to the second electronic device 3; and the transmission line 21 is coupled between the transmitter 20 and the receiver 22. In this embodiment, the transmission line 21 has at least one pair of twisted pairs, and may also be composed of a CAT-5 or CAT-6 twisted pair cable (Catometer 5 or category 6 cable), for example: Cat-5e, Cat- 6, Cat-6e, etc., which has four pairs of differential transmission lines, but not limited thereto. In fact, the signal between the transmitter 20 and the first electronic device 1 and between the receiver 22 and the second electronic device 3 can be transmitted through a high resolution multimedia interface (HDMI), a digital video interface (DVI) or a digital/analog audio interface. There are no specific restrictions on the transmission. In this embodiment, the digital video signal and the audio signal are from the same first electronic device 1 as an example.

As shown in FIG. 1 , the transmitter 20 includes at least a first filter module 201 and a second filter module 202 and a single-ended/differential signal conversion module 203 having different pass bands. The input end of the second filter module 202 is coupled to the single-ended/differential signal conversion module 203 and the output end of the second filter module 202 is coupled to the output end of the first filter module 201. In this embodiment, the first filter module 201 filters the pair of digital differential signals DD± received from the first electronic device 1 according to the first pass frequency band to output a pair of filtered digital differential signals FDD±. The single-ended/differential signal conversion module 203 converts the single-ended audio signal SA into a pair of differential audio signals DA±, and the second filter module 202 performs the pair of differential audio signals DA± according to the second passband. Filter to output a pair of filtered differential sound signals FDA±. The pair of filtered digital differential signals FDD± and the pair of filtered differential audio signals FDA± are combined into a pair of combined differential signals SD±, and the differential signal SD± is synthesized by one pair of differential transmission lines in the transmission line 21. Transfer to the receiver 22.

As shown in Fig. 3A, the figure is a schematic diagram of a synthetic differential signal. In Fig. 3A, only the positive differential is used to illustrate that the pair of filtered differential audio signals FDA± is an analog differential sound signal, and the pair of filtered digital differential signals FDD± are mounted on the pair of differential filters. The sound signal FDA± is on; with the second figure, the signal S _{TMDS (data)} in the 3A picture is the _{TMDS data} of the second data high-pass filtering unit 423 / the third data high-pass filtering unit 424 in FIG. 2 . The signal DD2±/DD3±, and the signal S _audio is the differential analog sound signal DAA1±/DAA2± passing through the first analog sound low-pass filtering unit 432/second analog sound low-pass filtering unit 433, and the signal S _mix is Mixed high-pass filtered digital data differential signal FDD2±/FDD3±. As shown in FIG. 3B, the positive differential signal indicates that the pair of filtered differential audio signals FDA± is a digital differential sound signal, and the pair of filtered digital differential signals FDD± are mounted on the pair of differential signals. As shown in Figure 2, the signal S _{TMDS(CLK) in} Figure 3B is the TMDS clock signal DC± of the clock high-pass filter unit 421, and the signal S _SPDIF is the digital sound low pass. The SPDIF signal of the filtering unit 431, and the signal S _{mix (FDC)} is a mixed high-pass filtered digital clock differential signal FDC±. In fact, the single-ended/differential signal conversion module 203 can include an operational amplifier (Aperture Amplifier) for converting the single-ended audio signal SA into a pair of differential audio signals DA± to increase the distance of the signal transmission. Avoid noise interference.

The receiver 22 includes at least a third filter module 221, a fourth filter module 222, and a differential/single-ended signal conversion module 223. The input end of the third filter module 221 is coupled to the input end of the fourth filter module 222, and the differential/single-ended signal conversion module 223 is coupled to the output end of the fourth filter module 222. After the receiver 22 receives the pair of combined differential signals SD± from the pair of differential transmission lines in the network route 21, the third filtering module 221 filters the pair of synthesized differential signals SD± according to the first passband. The logarithmic differential signal DD± is output to the second electronic device 3. The fourth filter module 222 filters the pair of combined differential signals SD± according to the second passband to output the pair of differential audio signals DA±, and the differential/single-ended signal conversion module 223 differentially pairs the pair The audio signal DA± is converted into a single-ended audio signal SA and output to the second electronic device 3. In fact, the differential/single-ended signal conversion module 223 can include an operational amplifier (Operational Amplifier). It should be noted that, in an embodiment, if the single-ended audio signal SA is an analog stereo signal, the amplitude of the restored single-ended audio signal SA may be the amplitude of the single-ended audio signal SA originally input to the transmitter 20. The same; if the single-ended voice signal SA is a digital SPDIF signal, the amplitude must be in accordance with the amplitude specifications acceptable for the Toslink transmission interface.

It should be noted that the first filter module 201 of the transmitter 20 and the third filter module 221 of the receiver 22 respectively use the first pass band to respectively the logarithmic differential signal DD± and the pair of synthesized differential signals. SD± performs high-pass filtering. In practical applications, if the logarithmic differential signal DD± is a pair of digital clock differential signals (such as TMDS clock signals), since the frequency range of the general digital clock differential signal is between 20 MHz and 225 MHz. Therefore, the first pass band of the present invention is set to a frequency range of 11 MHz or more, so that noise other than the logarithmic clock differential signal can be filtered by the high-pass filter program; if the logarithmic difference is The signal DD± is a pair of digital data differential signals (for example, TMDS data signals). Since the frequency range of the general digital data differential signal is between about 10 MHz and 1.125 GHz, the first pass frequency band of the present invention is set to The frequency range above 1.5 MHz enables noise outside the digital data differential signal to be filtered by the high-pass filter.

The second filter module 202 of the transmitter 20 and the fourth filter module 222 of the receiver 22 respectively use the second pass band to respectively lower the pair of differential audio signals DA± and the pair of synthesized differential signals SD±. Pass filter. In practical applications, if the pair of differential audio signals DA± is a pair of digital sound differential signals (for example, SPDIF signals), since the frequency range of the general digital sound differential signal is less than about 8 MHz, the second pass of the present invention The frequency band is set to a frequency range of 9 MHz or more, so that noise other than the logarithmic sound differential signal can be filtered by the low pass filtering program; if the pair of differential sound signals DA± is a pair of analog sound difference The motion signal (such as stereo signal, mono or left and right channels), because the frequency range of the analog sound differential signal that can be heard by the average human ear is less than 22KHz, the second pass band of the present invention is set to 530KHz or more. The frequency range is such that noise other than the analog analog differential signal can be filtered by the low pass filter.

Next, please refer to FIG. 2, which is a schematic diagram showing another embodiment of the signal transmission device of the present invention. As shown in FIG. 2, the signal transmission device STA includes a transmitter 4, a network route 5, and a receiver 6. The transmitter 4 is coupled to the digital image source 70, the digital sound source 71, and the analog sound source 72. The receiver 6 is coupled to the digital image output device 80, the digital sound output device 81, and the analog sound output device 82. The network route 5 includes four pairs of differential transmission lines L1 to L4 coupled between the transmitter 4 and the receiver 6. The digital image source 70 is a video output device having a high-resolution multimedia interface, such as a Blu-ray DVD player or a computer or a server having a digital image HDMI or DVI output, but not limited thereto; the digital sound source 71 is transmitted through an optical fiber ( Toslink) transmits SPDIF (Sony Philips Digital Interconnect Format) signal to transmitter 4; analog source 72 is a stereo generator for generating two-channel audio with analog format, left channel stereo signal and right channel stereo signal to transmission Device 4. The digital video output device 80 is a video display device having a high-resolution multimedia interface, such as a digital television with high image quality or a projection display device, but is not limited thereto. It should be noted that although in the present embodiment, the analog sound source 72 and the digital sound source 71 are simultaneously present, in practice, the embodiment shown in FIG. 2 is not limited. For example, only the digital sound source 71 may exist or only the analog sound source 72 may exist.

First, the transmitter 4 will be described in detail first. The transmitter 4 includes a buffer 40, a single-ended/differential signal conversion module 41, a first filter module 42, a second filter module 43, a differential signal transmitter 44, and an inductance element L. The inductor element L can also be replaced by a bead element, and the differential signal transmitter 44 can be an RJ-45 signal transmitter. This embodiment is a connection port of the RJ-45. The first filter module 42 includes four high-pass filter units 421-424 and the second filter module includes three low-pass filter units 431-433. The four high-pass filter units 421-424 are a clock high-pass filter unit 421, a first data high-pass filter unit 422, a second data high-pass filter unit 423, and a third data high-pass filter unit 424, respectively. The three low pass filtering units 431 to 433 are a digital sound low pass filtering unit 431, a first analog sound low pass filtering unit 432, and a second analog sound low pass filtering unit 433, respectively.

As shown in FIG. 2, the input terminals of the clock high-pass filter unit 421, the first data high-pass filter unit 422, the second data high-pass filter unit 423, and the third data high-pass filter unit 424 are all coupled to the buffer 40; the digital sound is low. The input ends of the pass filtering unit 431, the first analog sound low pass filtering unit 432 and the second analog sound low pass filtering unit 433 are all coupled to the single-ended/differential signal conversion module 41; the clock high-pass filtering unit 421, the first The output of the data high-pass filter unit 422, the second data high-pass filter unit 423, and the third data high-pass filter unit 424 are coupled to the differential signal transmitter 44; the output of the digital sound low-pass filter unit 431 is coupled to the clock high-pass The output end of the filtering unit 421 is connected to the differential signal transmitter 44. The output end of the first analog low-pass filtering unit 432 is coupled between the output of the second data high-pass filtering unit 423 and the differential signal transmitter 44. The output of the second analog sound low-pass filter unit 433 is coupled between the output of the third data high-pass filter unit 424 and the differential signal transmitter 44; one end of the inductance element (or magnetic bead element) L is coupled A ground terminal G, and the other end 44 is coupled to the first data between the high-pass filter means and the output terminal 422 of differential signal transmitter. It should be noted that the purpose of coupling to the ground G is to match the voltage levels of the transmitter and the receiver to avoid damage caused by an abnormal voltage difference between the transmitter and the receiver; and the way of grounding It is not limited by inductance or magnetic bead components.

It should be noted that the output end of the first analog low-pass filter unit 432 is not necessarily coupled to the output of the second data high-pass filter unit 423 and the differential signal transmitter 44, and the second analog sound is low-pass filtered. The output of the unit 433 does not have to be coupled between the output of the third data high-pass filter unit 424 and the differential signal transmitter 44. In fact, the output of the first analog low-pass filter unit 432 and the second analog low-pass filter unit 433 can be coupled between the output of the first data high-pass filter unit 422 and the differential signal transmitter 44. The two ends of the data high-pass filtering unit 423 and the differential signal transmitter 44 and between the output of the third data high-pass filtering unit 424 and the differential signal transmitter 44. The other of the three is coupled to the ground terminal G through an inductance element (or a bead element) L. This embodiment is coupled to the ground end G by the output end of the first data high-pass filter unit 422.

When the buffer 40 receives four pairs of differential signals (including a pair of digital clock differential signals DC± and three pairs of data differential signals DD1±, DD2± and DD3±) from the digital image source 70, the buffer 40 will enhance the strength of the four-digit differential signals DC±, DD1±, DD2±, and DD3± to increase the transmission distance. Then, the buffer 40 outputs the enhanced four-bit differential signals DC±, DD1±, DD2±, and DD3± to the clock high-pass filter unit 421 of the first filter module 42 and the first data high-pass filter unit. 422. The second data high-pass filtering unit 423 and the third data high-pass filtering unit 424. It is to be noted that the buffer 40 of the present invention is not an essential component, and it can be determined depending on the transmission distance. If the transmission distance is long, the buffer 40 can be used. If the transmission distance is short, it is not necessary to use .

The clock high-pass filtering unit 421 performs high-pass filtering on the logarithmic clock differential signal DC± according to the clock pass frequency band to output a pair of high-pass filtered digital clock differential signals FDC±; the first data high-pass filtering unit 422, the first The two data high-pass filtering unit 423 and the third data high-pass filtering unit 424 respectively perform high-pass filtering on the three pairs of digital data differential signals DD1±, DD2± and DD3± according to the data passing frequency band to respectively output three pairs of high-pass filtering digital data differences. The signals are FDD1±, FDD2± and FDD3±. In fact, since the frequency range of the general digital clock differential signal (for example, the TMDS clock signal) is between about 20 MHz and 225 MHz, the clock pass frequency band of the present invention is set to a frequency range of 11 MHz or more, so that the frequency range is Noise other than the digital clock differential signal DC± can be filtered by this high-pass filter. In addition, since the frequency range of the general digital data differential signal (for example, the TMDS data signal) is between about 10 MHz and 1.125 GHz, the data of the present invention is set to a frequency range of 1.5 MHz or more through the frequency band system, so that the logarithmic bit is made. Noise outside the data differential signal can be filtered by this high-pass filter.

On the other hand, when the single-ended/differential signal conversion module 41 receives the single-ended digital audio signal SDA and the two single-ended analog audio signals SAA1 and SAA2 from the digital sound source 71 and the analog sound source 72, the single-ended/differential signal The conversion module 41 converts the single-ended digital audio signal SDA and the two single-ended analog audio signals SAA1 and SAA2 into a pair of differential digital audio signals DDA± and two pairs of differential analog audio signals DAA1± and DAA2±, respectively. And outputting the pair of differential digital sound signals DDA± to the digital sound low-pass filtering unit 431, and outputting the two pairs of differential analog sound signals DAA1±, DAA2± to the first analog sound low-pass filtering unit 432 and the second analogy Sound low pass filtering unit 433.

When the digital sound low-pass filtering unit 431 receives the pair of differential digital sound signals DDA±, the digital sound low-pass filtering unit 431 low-pass filters the differential digital sound signal DDA± according to the digital sound through the frequency band to output A pair of low pass filtered differential digital sound signals FDDA± to the clock high pass filtering unit 421 and the differential signal transmitter 44, such that the pair of low pass filtered differential digital sound signals FDDA± can be coupled with the clock high pass filtering unit 421 The pair of high-pass filtered digital clock differential signals FDC± outputted are synthesized into a first pair of synthesized differential signals SD1±, and output to the first pair of differential transmission lines L1 in the network route 5 through the differential signal transmitter 44.

When the first analog sound low-pass filtering unit 432 receives the first pair of differential analog sound signals DAA1±, the first analog sound low-pass filtering unit 432 performs the first pair of differential analog sound signals DAA1± according to the analog sound passing frequency band. Low-pass filtering to output a first pair of low-pass filtered differential analog audio signals FDAA1± to the second data high-pass filtering unit 423 and the differential signal transmitter 44, such that the first pair of low-pass filtered differential analog audio signals FDAA1 The second pair of high-pass filtered digital data differential signals FDD2± outputted by the second data high-pass filtering unit 423 can be combined into a third pair of synthesized differential signals SD3±, and output to the network route 5 through the differential signal transmitter 44. The third pair of differential transmission lines L3.

Similarly, when the second analog sound low-pass filtering unit 433 receives the second pair of differential analog sound signals DAA2±, the second analog sound low-pass filtering unit 433 passes the frequency band to the second pair of differential analog sound signals according to the analog sound. The DAA2± performs low-pass filtering to output a second pair of low-pass filtered differential analog audio signals FDAA2± to the third data high-pass filtering unit 424 and the differential signal transmitter 44, so that the second pair of low-pass filtering differential analogy The audio signal FDAA2± can be combined with the third pair of high-pass filtered digital data differential signals FDD3± output by the third data high-pass filtering unit 424 into a fourth pair of synthesized differential signals SD4±, and output to the differential signal transmitter 44 through the differential signal transmitter 44. The fourth pair of differential transmission lines L4 in the network route 5. The first pair of high-pass filtered digital data differential signals FDD1± output by the first data high-pass filtering unit 422 are output to the second pair of differential transmission lines L2 in the network route 5 through the differential signal transmitter 44, and the pair of high-pass filters The digital data differential signal is represented by SD2±.

In fact, since the frequency range of the general digital sound differential signal (for example, SPDIF signal) is less than about 8 MHz, the digital sound of the present invention is set to a frequency range of 9 MHz or more through the frequency band system, so that the logarithmic sound differential signal DDA± Noise outside of the filter can be filtered by this low pass filter. In addition, since the frequency range of the analog sound differential signal (for example, the stereo signal) that can be heard by the general human ear is less than about 22 kHz, the analog sound passing frequency band of the present invention is set to a frequency range of 530 kHz or more, so that the two pairs of analog sounds are made. Noise other than the differential signals DAA1± and DAA2± can be filtered by this low-pass filter. By combining the high-pass and low-pass bands, the image signal and the audio signal can be combined without interfering with each other so that the image and sound signals can be transmitted simultaneously on the same pair of twisted pairs. In addition, the configuration of the embodiment of Fig. 2 allows sound (analog, digital or analogous to digital combination) and images (such as DVI or HDMI) to be transmitted over a single Cat 5. transmission line.

Next, the receiver 6 will be described in detail. As shown in FIG. 2, the receiver 6 includes a compensator 60, a differential/single-ended signal conversion module 61, a third filter module 62, a fourth filter module 63, a differential signal receiver 64, and an inductive component. L. The inductive component L can also be replaced by a magnetic bead component, and the differential signal receiver 64 can be an RJ-45 signal receiver. It should be noted that the third filter module 62 includes four high-pass filter units 621-624 and the fourth filter module includes three low-pass filter units 631-633. The four high-pass filtering units 621-624 are a clock high-pass filtering unit 621, a first data high-pass filtering unit 622, a second data high-pass filtering unit 623, and a third data high-pass filtering unit 624, respectively. The three low pass filtering units 631 to 633 are a digital sound low pass filtering unit 631, a first analog sound low pass filtering unit 632, and a second analog sound low pass filtering unit 633, respectively.

As shown in FIG. 2, the outputs of the clock high-pass filter unit 621, the first data high-pass filter unit 622, the second data high-pass filter unit 623, and the third data high-pass filter unit 624 are coupled to the compensator 60; the digital sound is low. The output of the pass filter unit 631, the first analog sound low pass filter unit 632 and the second analog sound low pass filter unit 633 are coupled to the differential/single-ended signal conversion module 61; the clock high-pass filter unit 621, the first The input ends of the data high-pass filter unit 622, the second data high-pass filter unit 623, and the third data high-pass filter unit 624 are all coupled to the differential signal receiver 64; the input end of the digital sound low-pass filter unit 631 is low in the first analog sound. The input of the pass filtering unit 632 and the input of the second analog sound low pass filtering unit 633 are also coupled to the three pairs of twisted pairs of the differential signal receiver 64.

The input end of the first analog low-pass filter unit 632 and the second analog sound low-pass filter unit 633 can be coupled between the input end of the first data high-pass filter unit 622 and the differential signal receiver 64, and the second data high-pass Both the input of the filtering unit 623 and the differential signal receiver 64 and between the input of the third data high-pass filtering unit 624 and the differential signal receiver 64. In this embodiment, the digital sound low pass filtering unit 631 is coupled between the input end of the clock high pass filtering unit 621 and the differential signal receiver 64; the input end of the first analog sound low pass filtering unit 632 is coupled to The input of the second data high-pass filter unit 623 and the differential signal receiver 64; and the input of the second analog sound low-pass filter unit 633 are also coupled to the input of the third data high-pass filter unit 624 and the differential The signal receiver 64 receives the combined differential signal. The other of the three is coupled to the ground terminal G through the inductance element L. In this embodiment, one end of the inductor element (or the bead element) L is coupled to the ground terminal G, and the other end is coupled between the input end of the first data high-pass filter unit 622 and the differential signal receiver 64; The method of grounding is not limited to the inductive component and the magnetic bead component. In this embodiment, the coupling relationship between the input ends of the first analog sound low pass filtering unit 632 and the second analog sound low pass filtering unit 633 corresponds to the first analog sound low pass filtering unit 432 and the second analog sound is low. The coupling relationship of the input ends of the filtering unit 433 is not limited thereto.

When the differential signal receiver 64 receives the first pair from the first pair of differential transmission lines L1, the second pair of differential transmission lines L2, the third pair of differential transmission lines L3, and the fourth pair of differential transmission lines L4 in the network route 5, respectively When the differential signal SD1±, the high-pass filtered digital data differential signal SD2±, the third pair of synthesized differential signals SD3±, and the fourth pair of synthesized differential signals SD4± are synthesized, the differential signal receiver 64 respectively synthesizes the first pair The differential signal SD1±, the high-pass filtered digital data differential signal SD2±, the third pair of synthesized differential signal SD3±, and the fourth pair of synthesized differential signal SD4± are transmitted to the clock high-pass filtering unit 621 and the first data high-pass filtering unit 622. The second data high-pass filtering unit 623 and the third data high-pass filtering unit 624.

The clock high-pass filtering unit 621 performs high-pass filtering on the first pair of synthesized differential signals SD1± according to the clock pass frequency band to output the logarithmic clock differential signal DC± to the compensator 60; the first data high-pass filtering unit 622, The second data high-pass filter unit 623 and the third data high-pass filter unit 624 respectively filter the digital signal differential signal SD2±, the third pair of composite differential signal SD3±, and the fourth pair of synthesized differential signals SD4± according to the data transmission band. High-pass filtering is performed to output the three-bit digital data differential signals DD1±, DD2±, and DD3± to the compensator 60, respectively. In fact, since the frequency range of the general digital clock differential signal (for example, the TMDS clock signal) is between about 20 MHz and 225 MHz, the clock pass frequency band of the present invention is set to a frequency range of 11 MHz or more, so that The pair of composite differential signals SD1± retains only the logarithmic clock differential signal DC± after passing through this high-pass filtering procedure. In addition, since the frequency range of the general digital data differential signal (for example, the TMDS data signal) is between 10 MHz and 1.125 GHz, the data of the present invention is set to a frequency range of 1.5 MHz or more through the frequency band system, so that the high-pass filtering digital position The data differential signal SD2±, the third pair of synthetic differential signals SD3±, and the fourth pair of synthesized differential signals SD4± pass through the high-pass filtering program and only retain the three pairs of digital data differential signals DD1±, DD2±, and DD3, respectively. ±.

Since the input end of the digital sound low-pass filter unit 631 is coupled between the input of the clock high-pass filter unit 621 and the differential signal receiver 64, the digital sound low-pass filter unit 631 will receive the first pair of synthesis. The differential signal SD1± is low-pass filtered by the first pair of synthesized differential signals SD1± according to the digital sound through the frequency band to output the pair of differential digital audio signals DDA± to the differential/single-ended signal conversion module 61. Since the input end of the first analog low-pass filter unit 632 is coupled between the input of the second data high-pass filter unit 623 and the differential signal receiver 64, the first analog sound low-pass filter unit 632 will receive And performing a low-pass filtering on the third pair of synthesized differential signals SD3± according to the analog sound through the frequency band to output the first pair of differential analog audio signals DAA1± to the differential/single-ended signal Conversion module 61. Similarly, since the input end of the second analog sound low-pass filter unit 633 is coupled between the input end of the third data high-pass filter unit 624 and the differential signal receiver 64, the second analog sound low-pass filter unit 633 The fourth pair of synthesized differential signals SD4± will be received and the fourth pair of synthesized differential signals SD4± will be low-pass filtered according to the analog sound through the frequency band to output a second pair of differential analog audio signals DAA2± to differential/ Single-ended signal conversion module 61.

In fact, since the frequency range of the general digital sound differential signal (for example, the SPDIF signal) is less than about 8 MHz, the digital sound of the present invention is set to a frequency range of 9 MHz or more through the frequency band system, so that the first pair of synthetic differential signals SD1± Only the pair of digital sound differential signals DDA± are retained by this low pass filtering procedure. In addition, since the analog sound differential signal that can be heard by the human ear (for example, the frequency range of the stereo signal is less than about 22 kHz, the analog sound passage frequency band of the present invention is set to a frequency range of 530 kHz or more, so that the third pair of synthetic differentials The signal SD3± and the fourth pair of synthesized differential signals SD4± pass only the two pairs of analog sound differential signals DAA1± and DAA2± after passing through the low-pass filtering procedure.

When the compensator 60 receives the logarithmic clock differential signal DC± and the three-digit digital data differential signals DD1±, DD2± and DD3±, due to the logarithmic clock differential signal DC± and the three pairs After the digital data differential signals DD1±, DD2± and DD3± are transmitted over a long distance, the signal strength is easily attenuated. Therefore, the compensator 60 will compensate the logarithmic clock differential signal DC± and the three logarithmic bits. The intensity of the data differential signals DD1±, DD2± and DD3±, and the compensated logarithmic clock differential signal DC± and the three-digit digital data differential signals DD1±, DD2± and DD3± are output to the digital position Image output device 80.

When the differential/single-ended signal conversion module 61 receives the pair of differential digital audio signals DDA±, the first pair of differential analog audio signals DAA1±, and the second pair of differential analog audio signals DAA2±, the differential/single The terminal signal conversion module 61 converts the pair of differential digital audio signals DDA±, the first pair of differential analog audio signals DAA1± and the second pair of differential analog audio signals DAA2± into the pair of single-ended digital audio signals, respectively. The first pair of single-ended analog audio signals SAA1 and the second pair of single-ended analog audio signals SAA2, and output the pair of single-ended digital audio signals SDA to the digital sound output device 81, and the first pair of single-ended analog audio signals The SAA1 and the second pair of single-ended analog sound signals SAA2 are output to the analog sound output device 82.

Please refer to FIG. 4, which is a schematic diagram showing the transmitter of the signal transmission device of the present invention. In this embodiment, a complex array of video and audio signal sources can be coupled through a switch 48. In fact, the switch 48 is integrated into the transmitter 4 or disposed outside the transmitter 4 to be coupled to the transmitter 4, which is not particularly limited. For example, in FIG. 4, there are two sets of video sources 70, 71, 72, and 70a, 71a, 72a are respectively coupled to the switch 48. Different video sources 70, 71, 72, or 70a, 71a, 72a can be selected by the control of the switch 48. After the selection, the processing methods of the video and audio signals provided by the video source 70, 71, 72, or 70a, 71a, 72a are the same as those shown in FIG. 2, and will not be described herein. In addition, the video and audio combining technology of the present invention can also be applied to a KVM switch or a KVM extender, that is, in a KVM switch or a KVM extender, as shown in FIG. 1 or FIG. 2 The architecture is to receive the sound and image provided by a computer coupled to the KVM switch or extender. The image signal is combined with the sound signal and transmitted on a transmission line having four pairs of twisted pairs.

Compared with the prior art, the signal transmission device according to the present invention performs high-pass filtering and low-pass filtering on the TMDS video signal and the digital and/or analog audio signal through filters having different pass bands, so that the transmitter and the receiver are The TMDS video signal and the digital and/or analog audio signals can be transmitted simultaneously through the high frequency band and the low frequency band of the mixed differential signal through a single network route without any interference between them. Therefore, the signal transmission device according to the present invention can effectively avoid the interference of the TMDS video signal during the transmission of the network route, thereby improving the signal transmission quality of the signal transmission device, since the signal transmission device does not need to additionally set other signal processing or decoding. The component can transmit TMDS video signals and digital and/or analog audio signals at the same time, which can effectively save hardware cost and signal processing time, and greatly enhance the market competitiveness of the signal transmission device.

The features and spirit of the present invention will be more apparent from the detailed description of the preferred embodiments. On the contrary, the intention is to cover various modifications and equivalents within the scope of the invention as claimed.

1. . . First electronic device

2, STA. . . Signal transmission device

3. . . Second electronic device

20, 4, 4a. . . Transmitter

twenty one. . . Transmission line

22, 6. . . receiver

201, 42. . . First filter module

202, 43. . . Second filter module

221, 62. . . Third filter module

222, 63. . . Fourth filter module

DD±. . . One-to-digit differential signal

FDD±. . . a pair of filtered digital differential signals

SA. . . Single-ended audio signal

DA±. . . a pair of differential sound signals

SD±. . . a pair of synthetic differential signals

FDA±. . . Pair of filtered differential sound signals

203, 41. . . Single-ended/differential signal conversion module

223. . . Differential/single-ended signal conversion module

70. . . Digital image source

71. . . Digital source

72. . . Analog source

80. . . Digital image output device

81. . . Digital sound output device

82. . . Analog sound output device

L1~L4. . . First pair of differential transmission lines ~ fourth pair of differential transmission lines

40. . . buffer

44. . . Differential signal transmitter

L. . . Inductive component

G. . . Ground terminal

421~424, 621~624. . . High pass filter unit

431~433, 631~633. . . Low pass filter unit

DC±. . . One-to-digit clock differential signal

FDC±. . . A pair of high-pass filtered digital clock differential signals

DD1±, DD2±, DD3±. . . Three pairs of digital data differential signals

FDD1±, FDD2±, FDD3±. . . Three pairs of high-pass filtered digital data differential signals

SDA. . . Single-ended digital audio signal

DDA±. . . a pair of differential digital sound signals

FDDA±. . . A pair of low pass filtered differential digital sound signals

SAA1, SAA2. . . Single-ended analog sound signal

DAA1±, DAA2±. . . Two pairs of differential analog sound signals

FDAA1±, FDAA2±. . . Two pairs of low pass filtered differential analog sound signals

SD1±~SD4±. . . The first pair of synthetic differential signals ~ the fourth pair of synthetic differential signals

5. . . Web route

48. . . Switcher

60. . . Compensator

61. . . Differential/single-ended signal conversion module

64. . . Differential signal receiver

S _TMDS(data) . . . TMDS data signal DD2±/DD3±

S _audio . . . Differential analog sound signal DAA1±/DAA2±

S _mix . . . Mixed high-pass filtered digital data differential signal FDD2±/FDD3±

S _{TMDS (CLK)} . . . TMDS clock signal DC±

S _SPDIF . . . SPDIF signal

S _{mix (FDC)} . . . Mixed high-pass filtered digital clock differential signal FDC±

1 is a schematic diagram of a signal transmission apparatus according to an embodiment of the present invention.

Figure 2 is a schematic diagram showing a signal transmission device according to another embodiment of the present invention.

Figures 3A and 3B are schematic diagrams of synthetic differential signals.

Figure 4 is a schematic illustration of the transmitter of the signal transmission device of the present invention.

1. . . First electronic device

2. . . Signal transmission device

3. . . Second electronic device

20. . . Transmitter

twenty one. . . Transmission line

twenty two. . . receiver

201. . . First filter module

202. . . Second filter module

221. . . Third filter module

222. . . Fourth filter module

DD±. . . One-to-digit differential signal

FDD±. . . a pair of filtered digital differential signals

SA. . . Single-ended audio signal

DA±. . . a pair of differential sound signals

SD±. . . a pair of synthetic differential signals

FDA±. . . Pair of filtered differential sound signals

203. . . Single-ended/differential signal conversion module

223. . . Differential/single-ended signal conversion module

Claims (28)

A signal transmission device includes at least: a transmitter that receives a pair of digital differential signals and a single-ended audio signal, the transmitter includes a single-ended/differential signal conversion module and one of different through frequency bands a filter module and a second filter module, wherein the input end of the second filter module is coupled to the single-ended/differential signal conversion module, and the output end of the second filter module is coupled to the first filter module The first filter module filters the logarithmic differential signal according to a first passband to output a pair of filtered digital differential signals, and the single-ended/differential signal conversion module uses the single-ended The sound signal is converted into a pair of differential sound signals, and the second filter module filters the pair of differential sound signals according to a second pass frequency band to output a pair of filtered differential sound signals, the pair of filtered digital differentials The signal is mounted on the pair of filtered differential audio signals to be combined into a pair of synthesized differential signals; a pair of differential transmission lines coupled to the transmitter for transmitting the pair of synthesized differential signals; and a receiver for From the right The mobile transmission line receives the pair of synthesized differential signals, and the receiver comprises a third filter module, a fourth filter module and a differential/single-ended signal conversion module, and the differential/single-ended signal conversion module is coupled. Connected to the output end of the fourth filter module, the third filter module filters the pair of composite differential signals according to the first pass frequency band to output the logarithmic differential signal, and the fourth filter module is configured according to the first The pair of synthesized differential signals are filtered by the frequency band to output the pair of differential audio signals, and the differential/single-ended signal conversion module converts the pair of differential audio signals into the single-ended audio signals. A transmitter includes at least: a first filtering module configured to filter a pair of digital differential signals output by an image source according to a first pass frequency band to output a pair of filtered digital differential signals; a differential signal conversion module for converting a single-ended audio signal into a pair of differential audio signals; and a second filter module having an input coupled to the single-ended/differential signal conversion module and The output end is coupled to the output end of the first filter module, and the second filter module filters the pair of differential audio signals according to a second pass band to output a pair of filtered differential audio signals, the pair of filtered digital differences The motion signal is mounted on the pair of filtered differential audio signals to be combined into a pair of synthesized differential signals. A receiver includes: a receiving end for receiving a pair of synthesized differential signals, wherein the pair of synthesized differential signals are synthesized by a pair of digital differential signals and a pair of differential sound signals, wherein the pair of differential signals are linked The first filter module is configured to filter the pair of composite differential signals according to a first pass frequency band to restore the logarithmic differential signal; and a second filter module The pair of differential signals are filtered according to a second passband to restore the pair of differential audio signals; and a differential/single-ended signal conversion module coupled to the output of the second filter module The end is configured to convert the pair of differential audio signals into a single-ended audio signal. A signal transmission device includes at least: a transmitter, comprising: a first filtering module, comprising a plurality of high-pass filtering units for respectively performing high-pass filtering on the complex logarithmic differential signals to output a complex pair a high-pass filtered digital differential signal; a single-ended/differential signal conversion module for converting at least one single-ended audio signal into at least one pair of differential audio signals; and a second filtering module including at least one low-pass a low-pass filter unit having an input end coupled to the single-ended/differential signal conversion module and an output end coupled to the output end of the first filter module, the at least one low-pass filter unit Performing low-pass filtering on the differential audio signal to output at least one pair of low-pass filtered differential audio signals, such that at least one pair of high-pass filtered digital differential signals of the plurality of high-pass filtered digital differential signals are mounted on the at least one pair of low Filtering the differential audio signal to form at least one pair of combined differential signals; the complex pair of differential transmission lines coupled to the transmitter for transmitting the at least one pair of combined differential signals and not at least one a high-pass filtered digital differential signal synthesized by the low-pass filtered differential audio signal; and a receiver comprising: a third filtering module comprising the plurality of high-pass filtering units for respectively a pair of combined differential signals and a high-pass filtered digital differential signal not synthesized with the at least one pair of low-pass filtered differential audio signals are high-pass filtered to restore the complex logarithmic differential signals; a fourth filter module includes The at least one low-pass filtering unit performs low-pass filtering on the at least one pair of synthesized differential signals to restore the at least one pair of differential audio signals; and a differential/ The single-ended signal conversion module is coupled to the output end of the fourth filter module for converting the at least one pair of differential audio signals into the at least one single-ended audio signal. The signal transmission device of claim 4, wherein in the transmitter, the plurality of logarithmic differential signals comprise a pair of digital clock differential signals and a plurality of logarithmic data differential signals, the plurality of high-pass signals The filtering unit comprises a clock high-pass filtering unit and a plurality of data high-pass filtering units, wherein the clock high-pass filtering unit performs high-pass filtering on the logarithmic clock differential signal according to a clock pass frequency band to output a pair of high-pass filtered digital time difference a plurality of data high-pass filtering units respectively high-pass filtering the plurality of digital data differential signals according to a data passing frequency band to output a plurality of high-pass filtered digital data differential signals, wherein the at least one single-ended audio signal includes a single And translating the digital audio signal into a pair of differential digital audio signals, wherein the at least one low pass filtering unit comprises a digital sound low pass filtering unit, the digital sound low pass filtering unit Performing low-pass filtering on the pair of differential digital sound signals according to a digital sound through the frequency band to output When low-pass filtering of the differential digital audio signal so that the digital high-pass filtering of the differential clock signal mounted above the pair of differential digital low-pass filtering the voice signal, to synthesize a first synthesized as a differential signal. The signal transmission device of claim 4, wherein in the transmitter, the plurality of logarithmic differential signals comprise a pair of digital clock differential signals and a plurality of logarithmic data differential signals, the plurality of high-pass signals The filtering unit comprises a clock high-pass filtering unit and a plurality of data high-pass filtering units, wherein the clock high-pass filtering unit performs high-pass filtering on the logarithmic clock differential signal according to a clock pass frequency band to output a pair of high-pass filtered digital time difference The plurality of data high-pass filtering units respectively perform high-pass filtering on the plurality of digital data differential signals according to a data transmission band to output a plurality of high-pass filtered digital data differential signals, wherein the at least one single-ended audio signal includes two The single-ended analog audio signal is converted into two pairs of differential analog audio signals by the single-ended/differential signal conversion module, and the at least one low-pass filtering unit includes two analog low-pass filtering units, and the two analog sounds are low. The pass filtering unit performs low-pass filtering on the two pairs of differential analog audio signals according to an analog sound passing frequency band The two pairs of low-pass filtered differential analog audio signals are respectively output, so that any two pairs of high-pass filtered digital data differential signals of the complex high-pass filtered digital data differential signals are respectively mounted on the two pairs of low-pass filtered differential analogs. Above the sound signal, the composite is a second pair of synthetic differential signals and a third pair of synthetic differential signals. The signal transmission device of claim 4, wherein the transmitter further comprises: a buffer coupled to the first filter module for enhancing the strength of the complex logarithmic differential signal And then output to the first filter module. The signal transmission device of claim 5, wherein the plurality of high-pass filtering units include a clock high-pass filtering unit and a plurality of data high-pass filtering units, wherein the clock high-pass filtering unit is in accordance with a temporary The first pair of synthesized differential signals are high-pass filtered to output the logarithmic clock differential signals, and the plurality of data high-pass filtering units respectively perform a low-pass filtering difference according to a data pass pair The high-pass filtered digital differential signal of the dynamic sound signal is high-pass filtered to output the digital data differential signal, and the at least one low-pass filtering unit comprises a digital sound low-pass filtering unit, and the digital sound low-pass filtering unit is in accordance with a digital sound The first pair of synthesized differential signals are low-pass filtered by the frequency band to output the pair of differential digital sound signals. The signal transmission device of claim 6, wherein the plurality of high-pass filtering units include a plurality of data high-pass filtering units to separately synthesize the differential signals for the second and third pairs. And high-pass filtering the digital differential signal synthesized by the at least one pair of low-pass filtered differential audio signals to output the complex logarithmic data differential signal, the at least one low-pass filtering unit comprising two analog low-pass signals a filtering unit, wherein the two analog low-pass filtering units respectively perform low-pass filtering on the second pair of synthesized differential signals and the third pair of synthesized differential signals according to an analog sound passing frequency band to respectively output the two pairs of differential analogies Sound signal. The signal transmission device of claim 4, wherein the high-pass filtering unit corresponding to the high-pass filtered digital differential signal that is not synthesized with the at least one pair of low-pass filtered differential audio signals is included in the transmitter The high-pass filtering unit is coupled to the ground, and is coupled to the high-pass filtering unit that receives the high-pass filtered digital differential signal that is not combined with the at least one pair of low-pass filtered differential audio signals. The signal transmission device according to claim 5 or 8, wherein the clock pass frequency band includes a frequency band greater than 11 MHz, and the data pass frequency band includes a frequency band greater than 1.5 MHz, and the digital sound passage frequency band includes less than 9 MHz. Frequency band. The signal transmission device according to claim 6 or 9, wherein the clock pass frequency band includes a frequency band greater than 11 MHz, and the data passage frequency band includes a frequency band greater than 1.5 MHz, and the analog sound passage frequency band includes less than 530 KHz. Frequency band. The signal transmission device of claim 12, wherein the receiver further comprises: a compensator coupled to the third filter module for compensating the complex logarithmic position through the third filter module The strength of the differential signal. A transmitter includes at least: a first filtering module, comprising a plurality of high-pass filtering units for respectively performing high-pass filtering on the complex logarithmic differential signals to output a complex pair of high-pass filtered digital differential signals; a single-ended/differential signal conversion module for converting at least one single-ended audio signal into at least one pair of differential audio signals; and a second filtering module including at least one low-pass filtering unit The input end is coupled to the single-ended/differential signal conversion module, and the output end thereof is coupled to the output end of the first filter module, and the at least one low-pass filter unit performs low on the at least one pair of differential audio signals Filtering to output at least one pair of low pass filtered differential audio signals, such that at least one pair of high pass filtered digital differential signals of the plurality of high pass filtered digital differential signals are mounted on the at least one pair of low pass filtered differential audio signals To form at least one pair of synthetic differential signals. The transmitter of claim 14, wherein the complex logarithmic differential signal comprises a pair of digital clock differential signals and a complex logarithmic data differential signal, the plurality of high pass filtering units including a clock high pass filter And a plurality of data high-pass filtering units, wherein the clock high-pass filtering unit performs high-pass filtering on the logarithmic clock differential signal according to a clock pass frequency band to output a pair of high-pass filtered digital clock differential signals, the plurality of data Qualcomm The filtering unit respectively performs high-pass filtering on the complex logarithmic data differential signal according to a data passing frequency band to output a plurality of high-pass filtered digital data differential signals, wherein the at least one single-ended audio signal includes a single-ended digital audio signal, and The single-ended/differential signal conversion module is converted into a pair of differential digital sound signals, and the at least one low-pass filtering unit includes a digital sound low-pass filtering unit, and the digital sound low-pass filtering unit passes the frequency band according to a digital sound. Low-pass filtering the differential digital sound signal to output a pair of low-pass filtered differential digital sounds Number, the differential clock signal of a high pass filter mounted on top of the digital low-pass filtering of the differential digital audio signal, to synthesize a first synthesized as a differential signal. The transmitter of claim 15, wherein in the transmitter, the complex logarithmic differential signal comprises a pair of digital clock differential signals and a plurality of logarithmic data differential signals, the plurality of high pass filters The unit comprises a clock high-pass filtering unit and a plurality of data high-pass filtering units, wherein the clock high-pass filtering unit performs high-pass filtering on the logarithmic clock differential signal according to a clock pass frequency band to output a pair of high-pass filtered digital clock differentials. The plurality of data high-pass filtering units respectively perform high-pass filtering on the plurality of digital data differential signals according to a data transmission band to output a plurality of high-pass filtered digital data differential signals, wherein the at least one single-ended audio signal includes two orders The analog audio signal is converted into two pairs of differential analog audio signals by the single-ended/differential signal conversion module, and the at least one low-pass filtering unit includes two analog low-pass filtering units, and the two analog sounds are low-pass. The filtering unit performs low-pass filtering on the two pairs of differential analog audio signals according to an analog sound passing frequency band, respectively Outputting two pairs of low-pass filtered differential analog sound signals, wherein the two pairs of high-pass filtered digital data differential signals of the high-pass filtered digital data differential signals are respectively mounted on the two pairs of low-pass filtered differential analog sound signals In the above, the synthesis is a second pair of synthetic differential signals and a third pair of synthetic differential signals. The transmitter of claim 15 wherein the high pass filtering unit corresponding to the high pass filtered digital differential signal not synthesized with the at least one pair of low pass filtered differential audio signals is coupled to the ground. The transmitter of claim 15, wherein the clock-passing frequency band comprises a frequency band greater than 11 MHz, and the data passing frequency band comprises a frequency band greater than 1.5 MHz, and the digital sound passing frequency band comprises a frequency band less than 9 MHz. The signal transmission device of claim 16, wherein the clock-passing frequency band includes a frequency band greater than 11 MHz, and the data passing frequency band includes a frequency band greater than 1.5 MHz, and the analog sound passing frequency band includes a frequency band less than 530 kHz. . The transmitter of claim 20, further comprising: a buffer coupled to the first filter module for enhancing the strength of the complex logarithmic differential signal, and then outputting the The first filter module. The transmitter of claim 14, further comprising a switch coupled to the first filter module and the single-ended/differential signal conversion module, the switch further The plurality of sets of audio and video signal sources are coupled to each other, and each of the sets of video and audio signal sources provides the complex logarithmic differential signal and the at least one pair of differential audio signals, and the switch is controlled by the plurality of sets of video signal sources by switching control a set of video signal sources for transmitting the complex logarithmic differential signal and the at least one pair of differential audio signals provided by the selected video signal source to the first filter module and the single-ended/differential signal conversion Module. A receiver includes: a receiving end for receiving at least one pair of combined differential signals and at least one pair of high-pass filtered digital differential signals, each pair of synthesized differential signals being a pair of differential voice signals and a pair of digits a differential signal synthesis, wherein the logarithmic differential signal is mounted on the pair of differential audio signals; a first filter module includes a plurality of high-pass filter units for respectively pairing the at least one pair The composite differential signal and the at least one pair of high-pass filtered digital differential signals are high-pass filtered to restore the complex logarithmic differential signal; and the second filtering module includes at least one low-pass filtering unit for Performing low-pass filtering on the at least one pair of synthesized differential signals to restore the at least one pair of differential audio signals; and a differential/single-ended signal conversion module coupled to the output end of the second filter module Converting the at least one pair of differential audio signals into at least one single-ended audio signal. The receiver of claim 21, wherein the at least one pair of synthesized differential signals comprises a first pair of synthesized differential signals, the first pair of synthesized differential signals being a pair of differential digital sound signals Synthesizing with a pair of digital clock differential signals, the plurality of high-pass filtering units include a clock high-pass filtering unit and at least one data high-pass filtering unit, the clock high-pass filtering unit synthesizing the first pair according to a clock pass frequency band The differential signal is high-pass filtered to output the logarithmic clock differential signal, and the at least one data high-pass filtering unit performs high-pass filtering on the at least one high-pass filtered digital differential signal according to a data passing frequency band to output the digital data differential a signal, the at least one low pass filtering unit includes a digital sound low pass filtering unit, wherein the digital sound low pass filtering unit performs low pass filtering on the first pair of synthesized differential signals according to a digital sound through the frequency band to output the pair of differences Dynamic digital sound signal. The receiver of claim 21, wherein the at least one pair of synthesized differential signals comprises a second pair of synthesized differential signals and a third pair of synthesized differential signals, the second pair of synthesized differential signals And the third pair of synthetic differential signals are respectively synthesized by a pair of differential analog audio signals and a pair of digital data differential signals, the at least one high-pass filtering unit includes a plurality of data high-pass filtering units, and the plurality of data high-pass The filtering unit respectively performs high-pass filtering on the second pair of synthesized differential signals, the third pair of synthesized differential signals, and the at least one pair of high-pass filtered digital differential signals according to a data transmission band to output a complex logarithmic data differential signal. The at least one low-pass filtering unit includes two analog low-pass filtering units, and the two analog-type low-pass filtering units respectively perform the second pair of synthesized differential signals and the third pair of synthesized differential signals according to an analog sound passing frequency band. Low pass filtering to output the two pairs of differential analog sound signals, respectively. The receiver of claim 21, wherein the high pass filtering unit corresponding to the high pass filtered digital differential signal not synthesized with the at least one pair of low pass filtered differential audio signals is coupled to the ground. The receiver of claim 22, wherein the clock-passing frequency band comprises a frequency band greater than 11 MHz, and the data passing frequency band comprises a frequency band greater than 1.5 MHz, and the digital sound passing frequency band comprises a frequency band less than 9 MHz. The receiver of claim 23, wherein the clock-passing frequency band comprises a frequency band greater than 11 MHz, and the data passing frequency band comprises a frequency band greater than 1.5 MHz, and the analog sound passing frequency band comprises a frequency band less than 530 kHz. The receiver of claim 21, further comprising: a compensator coupled to the second filter module for compensating for the strength of the complex logarithmic differential signal passing through the second filter module .