TWI466457B - Wireless transmission interface for video transmission and power control method - Google Patents

Description

Wireless transmission interface for transmitting video and power control method thereof

The present invention relates to a wireless transmission interface, and more particularly to a wireless transmission interface for transmitting video, a power control method thereof, and a computer or mobile device using the wireless transmission interface.

With the advancement of technology, traditional heavy-duty and bulky desktop computers have gradually been replaced by thin and light notebooks or other mobile devices. Because the notebook computer is portable, the external display device cannot communicate with the notebook computer as a medium through a fixed connection line. In other words, the external display device does not move with the notebook computer, so the notebook computer cannot continue to be connected to the external display device due to the problem of the length of the connection cable.

At present, the computer and the display device can be connected through a Video Graphic Array (VGA) cable, a Digital Visual Interface (DVI) cable or a High Definition Multimedia Interface cable. In general, current display devices have a VGA cable interface and an HDMI cable interface. The signal used in the VGA format is an analog signal, so as the distance increases, the distortion of the signal in the VGA cable will be larger, resulting in severe data loss. HDMI 1.3 is the latest HDMI format, which can transmit uncompressed video and audio at a transmission rate of 10.2 billion bits per second (10.2 Gbit/sec), but the price of HDMI cable using HDMI 1.3 format is expensive. And the reason why it cannot be folded, but also the distance between the computer and the display device cannot be too long.

The invention also provides a wireless transmission interface for transmitting video, which comprises an input interface, a transceiver chipset, x amplifier circuits, x antennas and a control circuit. The input interface is configured to receive video data that the local end device wants to transmit to the remote display device, and correspondingly output the video signal. The transceiver chipset has an input for receiving a video signal and has x modulated signal outputs. Each amplifier circuit has an input end and an output end, and an input end of each amplifier circuit is coupled to one of the x modulation signal output ends. Each antenna is coupled to one of the output terminals x x of the amplifier circuits. The control circuit controls the transceiver chipset to perform the video signal according to the signal format, the modulation mode, the video image resolution, the power state of the local device, the transmission channel quality parameter, the user control signal or the feedback control signal corresponding to the video signal. Signal processing to generate y modulated signals to y modulated signal output terminals, and the control circuit according to the signal format corresponding to the video signal, modulation mode, video image resolution, local end device power status, transmission channel quality parameters, a user control signal or feedback control signal y a modulated signal output y of the amplifier circuits corresponding switch, and uses y y th transmission antennas corresponding to the modulation signal to the radio path, wherein y is less than Equal to x and greater than 0.

In addition, the present invention also provides a local end device having computing power and communication capability for transmitting video data to a remote display device, and the local end device has the above wireless transmission interface.

The invention provides a power control method for a wireless transmission interface, wherein a wireless transmission interface is used for transmitting video data of a local end device to a remote display device, wherein the local end device has x transmission paths, and each transmission path has a transmission path. Antenna with an amplifier circuit. First, the video data is converted into a video signal. Then, the minimum antenna usage number s is determined according to the video format of the video signal, the resolution of the video picture, and the modulation mode. Thereafter, the power supply status of the local terminal device, the quality parameters of a transmission channel, a user control signal or feedback control signal determines the number of antennas used y, and the video signal subjected to signal processing to generate a modulated signal y to y antennas. Then, according to the signal format corresponding to the video signal, the modulation mode, the resolution of the video signal, the power status of the local device, the transmission channel quality parameter, the user control signal or the feedback control signal, the y antennas are controlled. The switching or gain of the y amplifier circuits. Finally, the signals received by it are carried to the wireless channel using y antennas, where y is less than or equal to x and greater than zero.

Based on the above, the wireless transmission interface and the power control method thereof provided by the embodiments of the present invention can enable the computer or mobile device using the wireless transmission interface to transmit the video data to the remote display device, and the wireless transmission interface The number of antennas used, the amplifier gain, and the amplifier's switches can all be controlled by a variety of different parameters, enabling the computer or mobile device to save power, while allowing the user to view the computer or action through the remote display device. The video played by the device to enjoy high quality video.

The above described features and advantages of the present invention will be more apparent from the following description.

Embodiments of the present invention provide a wireless transmission interface for transmitting video. This wireless transmission interface is suitable for all types of computers and mobile devices, and can support a variety of different video formats. The above-described wireless transmission interface will be further described in the following text, but it should be noted that the following description is only an embodiment of the present invention and is not intended to limit the present invention.

Please refer to FIG. 1. FIG. 1 is a schematic diagram of a video transmission system according to an embodiment of the present invention. In this video transmission system 10, the notebook computer 100 is a local end device, and the external television 120 is a remote display device. The notebook computer 100 and the television 120 are connected to each other by way of wireless communication, and the video data is transmitted. The wireless transmission interface of the notebook computer 100 has a multi-antenna transceiver device 102 having a plurality of antennas and signal processing devices. The signal processing device of the antenna transceiver device 102 is configured to modulate (and possibly include encoding or filtering) the video data to generate more than one modulated signal to the antenna of the multi-antenna transceiver device 102. Next, the antenna of the multi-antenna transceiver 102 is used to carry the modulated signal it receives to the wireless channel. The wireless transmission interface of the television 120 has a multi-antenna transceiver 122 having a plurality of antennas and signal processing means. At least one antenna of the antenna transceiver 122 is configured to receive the modulated signal from the wireless channel, and send the received modulated signal to a signal processing device of the antenna transceiver 122 for demodulation (and possibly even decoding, filtering, and Equalization) to obtain video data transmitted by the notebook computer 100. In addition, it should be noted that the multi-antenna transceivers 102 and 122 of FIG. 1 are located outside the notebook computer 100 and the television 102, but in fact, Vary Large Scale Integrated Circuit (VLSI) technology can also be used. It is implemented in the internal chip of the notebook computer 100 and the television 102.

The modulation method used by the multi-antenna transceivers 102 and 122 is not particularly limited, but it can adopt high-order modulation of Orthogonal Frequency Division Modulation (OFDM) under the requirement of high transmission rate. For example, 256 points (or even 512 points or 1024 points) of Quadrature Amplitude Modulation (QAM), so that each antenna can achieve a transmission of about 320 megabits per second (320 Mbit/sec) Rate (ie has a bandwidth of 40 megahertz (40 MHz)). In addition, the frequency bands used by the multi-antenna transceivers 102 and 122 for video data transmission are also unlimited, and they can use 2.4 billion to 2.5 billion Hz (2.4 GHz to 2.5 GHz) open bands for industrial, scientific, and medical use (Industrial) , Science, Medical Band, ISM Band) or use the 5 billion Hertz (5 GHz) band.

When the modulation method used by the multi-antenna transceivers 102 and 122 uses the 256-point QAM of the above OFDM, if there is a need to transmit 30 720×720 pixel images per second (720P@30fps) video, then it is required. A bandwidth of 720 Mbit/sec requires at least two antennas for transmission. If there is a need to transmit 30 1080 × 1080 pixel images per second (1080P@30fps) video, then about 1.5Gbit/sec bandwidth is required, so at least four antennas are needed for transmission.

The multi-antenna transceiver 102 determines the multi-antenna transceiver 102 according to the video format, the resolution of the video screen, the modulation mode, the power status, the measured channel transmission quality parameter, the feedback control signal, or the user control signal. The number of antennas used or the gain value of the amplifier used to thereby turn off the antenna that is not needed, reduce the amplifier gain, or turn off the amplifier, thereby saving power consumed by the notebook computer 100.

The multi-antenna transceiver 122 can estimate the bit error rate or packet loss rate and generate a feedback control signal to the multi-antenna transceiver 102 based on the bit error rate or the packet loss rate. The multi-antenna transceiver 102 then determines the number of antennas used by the multi-antenna transceiver 102 or the gain of the amplifier used based on the feedback control signal. When the user is watching video, if you want to switch the video format (for example, switch from VGA to HDMI), modulation mode (for example, switch from 256-point QAM to 64-point QAM) or the resolution of the video screen (for example, switch from 720P@30fps). Up to 1080P@30fps), the user can use the remote controller to generate a user control signal, and directly transmit the user control signal to the multi-antenna transceiver device 102, or to the multi-antenna transceiver device 122, and then transmit and receive by multiple antennas. Device 122 transmits this user control signal to multi-antenna transceiver 102. After the multi-antenna transceiver 102 receives the user control signal, the multi-antenna transceiver 102 determines the number of antennas used by the multi-antenna transceiver 102 or the gain value of the amplifier used based on the user control signal.

In addition, the multi-antenna transceiver 102 itself can also measure channel transmission quality parameters to determine the number of antennas used by the multi-antenna transceiver 102 or the gain values of the amplifiers used, wherein the channel transmission quality includes the estimated bits. Error rate or packet loss rate, etc. The power source used by the notebook computer 100 may be an internal battery or an external power supply device (for example, a transformer connected to the socket). If the notebook computer 100 is powered by an internal battery, the multi-antenna transceiver device 102 may reduce the number of antennas used, Reducing the amplifier gain or turning off some of the amplifiers, if the notebook computer 100 is powered by an external power supply, the multi-antenna transceiver 102 may increase the number of antennas used, increase the amplifier gain, or turn on some or all of the amplifiers. It is worth mentioning that if the notebook computer 100 is powered by an internal battery and the power is insufficient, the multi-antenna transceiver 102 may even reduce the number of antennas used, reduce the amplifier gain, or turn off part of the amplifier.

The video format, the resolution and modulation mode of the video picture determine the minimum number of antennas to be used. In addition, the resolution and modulation of the video format and video picture can also be adjusted by adjusting the amplifier gain or controlling the amplifier to turn off. Basis. According to the teaching principle of the communication, the technique of antenna diversity can reduce the error rate during data transmission. Therefore, the multi-antenna transceiver 102 determines the minimum antenna to be used according to the video format, the resolution and the modulation mode of the video picture. In addition to the number, the number of antennas used can be greater than the minimum number of antennas to increase the accuracy of video data transmission.

Although the above describes how the multi-antenna transceiver 102 determines the multi-antenna transmission and reception according to the video format, the resolution of the video screen, the modulation mode, the power supply status, the measured channel transmission quality parameter, the feedback control signal, or the user control signal. The number of antennas used by the device 102 or the individual values of the gain values of the amplifiers used, but the invention is not limited thereto. The above parameters for determining the number of antennas used by the multi-antenna transceiver 102 or the gain value of the amplifier used may have priority. For example, when the video format, the resolution and modulation mode of the video picture determine the minimum required to be used. After the number of antennas, the feedback control signal, the measured channel transmission quality parameter, the feedback control signal or the user control signal can only increase the number of antennas used, and cannot reduce the number of antennas used.

In addition, the video format may be in VGA, HDMI or DVI format. In other words, the video signal may be a low voltage differential signal (LVDS) or an HDMI signal. In short, the format and signal type of the video are not intended to limit the invention. In addition, although the above-mentioned local device is exemplified by the notebook computer 100, it is not intended to limit the present invention. In other words, the above-mentioned local device can also be a general desktop computer, a smart phone, a personal digital assistant (PDA) device or an electronic device with communication and computing functions. Similarly, although the above-mentioned remote display device is exemplified by the television 120, it is not intended to limit the present invention. The remote display device may also be a screen, a projection device or other electronic device having a display function.

Next, please refer to FIG. 2. FIG. 2 is a circuit diagram of a wireless transmission interface for transmitting video according to an embodiment of the present invention. The wireless transmission interface 20 is implemented in any of the above-described electronic devices having communication and computing functions, such as a notebook computer. The wireless transmission interface 20 includes input interfaces 200, 202, transceiver chipset 220, amplifier circuits 240, 242, 244, 246, 248, multiple antennas 260, 262, 264, 266 and control circuitry 270. The output ends of the input interfaces 200 and 202 are respectively coupled to the two input terminals IN1 and IN2 of the transceiver chip set 220. The output terminals OUT1 to OUT4 of the transceiver chip set 220 are coupled to the inputs of the amplifier circuits 240, 242, 244, and 246. The output of the amplifier circuit 248 is coupled to the input terminal IN3 of the transceiver chip set 220, and the antennas 260, 262, 264, and 266 are coupled to the output ends of the amplifier circuits 240, 242, 244, and 246, respectively, at least one of the antennas. The 262 is further coupled to the input of the amplifier circuit 248.

It is to be noted that although the embodiment of FIG. 2 uses only one amplifier circuit 248 and antenna 262 for reception, for example, receiving the aforementioned feedback control signal or user control signal, the present invention is not limited thereto. According to the teaching principle of the communication, the technique of antenna clustering can reduce the error rate during data transmission. Therefore, if the correctness of the signal received by the transceiver chipset 220 is increased, the amplifier circuit for amplifying the received signal can be added to other antenna paths. And use other antennas for reception. In short, the embodiment of Figure 2 is for convenience of description and is not intended to limit the invention.

The turn-off and turn-on of the amplifier circuits 240, 242, 244, and 246 described above can be controlled by the wireless transmission interface 20, and even the gain values of the amplifier circuits 240, 242, 244, 246, and 248 can be controlled by the wireless transmission interface 20. Additionally, the above control may be accomplished by control circuitry 270, which may be implemented in transceiver chipset 220 or as a separate circuit in wireless transmission interface 20. The input interfaces 200 and 202 are configured to convert the received video data into a signal format used by the corresponding video format, and the transceiver chip set 202 includes a modulation/demodulator, a multiplexer, an encoder/decoder, etc. The module 202 is configured to modulate (or even include encoding or filtering) a signal output by the input interface 200 or 202 to generate one or more modulated signals for amplifying the turned-on amplifier circuit and allowing the turned-on amplifier The antenna corresponding to the circuit carries the amplified modulated signal.

In the embodiment of FIG. 2, the local device transmits video data to be transmitted to the input interfaces 200 and 202 according to the currently used video format. For example, the input interface 200 cooperates with the VGA format. The video data is converted into an LVDS signal, and the input interface 202 converts the video data into an HDMI signal in accordance with the HDMI format. The control circuit 270 of the wireless transmission interface 20 determines the minimum number of antennas to use based on the modulation mode, the video format, and the resolution of the video picture.

For example, if the modulation mode is OFDM and 256-QAM and the resolution of the video picture is fixed, when the video format is VGA format, the transceiver chip set 220 modulates the LVDS signal (and may even include encoding or filtering) to generate The two modulated signals are amplified by two amplifier circuits (e.g., 240 and 242) and that two antennas (e.g., 260 and 262) carry the outputs of the amplifier circuits (e.g., 240 and 242) to the wireless channel. For example, if the modulation mode is OFDM and 256-QAM and the resolution of the video picture is fixed, when the video format is the HDMI format, the transceiver chip set 220 modulates the HDMI signal according to the control of the control circuit 270 (and may even include encoding). Or filtering) to generate 4 modulated signals for amplification of the four amplifier circuits 240, 242, 244 and 246, and for the four antennas 260, 262, 264 and 266 to output the amplifier circuits 240, 242, 244 and 246 Carry to the wireless channel.

In addition, in the embodiment of FIG. 2, the control circuit 270 of the wireless transmission interface 20 also determines the amplifier circuit 240 according to the local end device power condition, the measured channel transmission quality parameter, the feedback control signal, or the user control signal. Gains of 242, 244, 246, and 248. At the same time, if the local end device power supply is sufficient, and the measured channel transmission quality parameter indicates that the channel transmission quality is not good, then the antenna data larger than the minimum antenna usage number can be used for the transmission of the video data to improve the far end. The correctness of the video data received by the display device. Similarly, if the local end device power supply is sufficient, and the control signal or the user control signal indicates that more antennas are to be used, the antenna data may be transmitted using an antenna larger than the minimum antenna usage number. To improve the accuracy of the video data received by the remote display device.

In the embodiment of Figure 2, if the amplifier circuit is turned off, the antenna of the corresponding path is also turned off entirely. In other words, in Figure 2, if the antenna is selected for use, the corresponding amplifier circuit will also be turned on. However, sometimes the modulation signal to be delivered to the antenna does not necessarily require amplification of the amplifier circuit. Therefore, the embodiment of FIG. 3 provides a more flexible wireless transmission interface. Another embodiment of the wireless transmission interface will be described in detail below.

Please refer to FIG. 3. FIG. 3 is a circuit diagram of a wireless transmission interface according to an embodiment of the present invention. The wireless transmission interface 30 includes an input interface 300, 302, a transceiver chip set 320, amplifier circuits 340, 342, 344, 346, 348, a plurality of antennas 360, 362, 364, 366, a plurality of switches 380, 382, 384, 386 And control circuit 370. The output terminals of the input interfaces 300 and 302 are respectively coupled to the two input terminals IN1 and IN2 of the transceiver chip set 320. The output terminals OUT1 to OUT4 of the transceiver chip group 320 are coupled to the input of the amplifier circuits 340, 342, 344 and 346. The output of the amplifier circuit 348 is coupled to the input terminal IN3 of the transceiver chip set 320, and the antennas 360, 362, 364, and 366 are coupled to the output ends of the amplifier circuits 340, 342, 344, and 346, respectively, at least one of the antennas. The 362 is further coupled to the input of the amplifier circuit 348.

In addition, the short circuit and the open circuit of the switches 380, 382, 384, and 386 are controlled by the control circuit 370 of the wireless transmission interface 30. The two ends of the switch 380 are coupled to the input end and the output end of the amplifier circuit 340, and the two ends of the switch 382. The terminal is coupled to the input end and the output end of the amplifier circuit 342. The two ends of the switch 384 are coupled to the input end and the output end of the amplifier circuit 344. The two ends of the switch 386 are coupled to the input end and the output end of the amplifier circuit 346.

The closing and opening of the above-mentioned amplifier circuits 340, 342, 344 and 346 can be controlled by the control circuit 370 of the wireless transmission interface 30, and even the gain values of the amplifier circuits 340, 342, 344, 346 and 238 can be wirelessly transmitted. Control circuit 370 of 30 controls. The input interfaces 300 and 302 are configured to convert the received video data into a signal format used by the corresponding video format, and the transceiver chip set 302 includes a modulation/demodulator, a multiplexer, an encoder/decoder, etc. The module 302 modulates (or may even include encoding or filtering) the signal output by the input interface 300 or 302 according to the control of the control circuit 370 to generate one or more modulated signals for amplifying the turned-on amplifier circuit, and Let the antenna corresponding to the turned-on amplifier circuit carry the amplified modulated signal.

The difference from the embodiment of FIG. 2 is that the embodiment of FIG. 3 transmits wirelessly when the power supply used by the local device is insufficient for internal battery or battery power, or when the modulation signal is not required at all. The control circuit 370 of the interface 30 controls the switch of the path corresponding to the antenna to be turned into a short circuit state, and turns off the corresponding amplifier circuit, thereby saving power consumed by the local end device. However, when the power supply used by the local device is an external power supply device or the battery power is sufficient, or when the modulation signal is not needed at all to ensure the reception quality, the control circuit 370 of the wireless transmission interface 30 controls the being turned on. The switch of the path corresponding to the antenna is in an open state, and the corresponding amplifier circuit is turned on.

For example, if the modulation mode is OFDM and 256-QAM, the resolution of the video picture is fixed, and the local device uses its internal battery to supply power, when the video format is VGA format, the transceiver chip set 320 will output the LVDS signal. Modulating (and possibly encoding or filtering) to generate two modulated signals through shorted switches (eg, 380 and 382) and having two antennas (eg, 360 and 362) carrying the modulated signal to the wireless channel The amplifier circuits 340, 342, 344 and 346 are all turned off by the control circuit 370 of the wireless transmission interface 30 to save power consumed by the battery. For example, if the modulation mode is OFDM and 256-QAM and the resolution of the video picture is fixed, and the local device is powered by an external power supply device, when the video format is the HDMI format, the transceiver chip set 320 performs the HDMI signal. Modulation (and possibly even encoding or filtering) to generate 4 modulated signals for amplification of 4 amplifier circuits 340, 342, 344 and 346, and 4 antennas 360, 362, 364 and 366 to amplifier circuit 340, The outputs of 342, 344, and 346 are carried to the wireless channel, at which point control circuit 370 of wireless transmission interface 30 controls switches 380, 382, 384, and 386 to assume an open state.

Next, please refer to FIG. 4. FIG. 4 is a circuit diagram of a wireless transmission interface according to an embodiment of the present invention. The wireless transmission interface 40 includes an input interface 400, 402, a transceiver chip set 420, amplifier circuits 440, 442, 444, 446, 448, a plurality of antennas 460, 462, 464, 466, variable power groups 480, 482, 484, 486 and control circuit 470. The output terminals of the input interfaces 400 and 402 are respectively coupled to the two input terminals IN1 and IN2 of the transceiver chip set 420. The output terminals OUT1 to OUT4 of the transceiver chip group 420 are coupled to the input of the amplifier circuits 440, 442, 444 and 446. The output of the amplifier circuit 448 is coupled to the input terminal IN3 of the transceiver chip set 420, and the antennas 460, 462, 464, and 466 are coupled to the output ends of the amplifier circuits 440, 442, 444, and 446, respectively, at least one of the antennas. The 462 is further coupled to the input of the amplifier circuit 248.

In addition, the resistance values of the variable resistors 480, 482, 484, and 486 are controlled by the control circuit 470 of the wireless transmission interface 40. The two ends of the switch 480 are coupled to the input end and the output end of the amplifier circuit 440. The two ends are coupled to the input end and the output end of the amplifier circuit 442. The two ends of the switch 484 are coupled to the input end and the output end of the amplifier circuit 444. The two ends of the switch 486 are coupled to the input end and the output end of the amplifier circuit 446. .

Different from FIG. 2, the embodiment of FIG. 4 adds a negative feedback resistor (ie, the above-mentioned variable resistor) between the output and the input of each amplifier circuit, and the gain of each amplifier circuit can be wirelessly In addition to the direct control of the control circuit 470 of the transmission interface 40, the gain of each amplifier circuit can also be adjusted by adjusting the variable electrical resistance by the control circuit 470. If the gain of each of the above amplifier circuits is a fixed gain, the variable resistor of the embodiment of Fig. 4 can be utilized. The gain of each amplifier circuit is changed by adjusting the variable resistor. In other words, each of the amplifier circuits of FIG. 4 may be an amplifier circuit with adjustable gain or an amplifier circuit with fixed gain. However, to adjust the gains of the amplifier circuits of FIGS. 2 and 3, the amplifier circuits of FIGS. 2 and 3 Must be an amplifier circuit with adjustable gain.

After the wireless transmission interface provided by the embodiment of the present invention is introduced, an embodiment of the power supply control method used in the wireless transmission interface described above will be described with reference to FIG. Please refer to FIG. 5. FIG. 5 is a flowchart of a power control method for a wireless transmission interface according to an embodiment of the present invention. First, in step S510, the input interface converts the video data into a video signal, and the signal format of the video signal is a signal format corresponding to the video format of the input interface specification, wherein the video data is transmitted to the remote end by the local device. The video of the display device is displayed, and the signal format specified by the input interface can be an HDMI or LVDS signal format.

In step S520, the control circuit of the wireless transmission interface determines the minimum antenna usage number s according to the video format, the resolution and the modulation mode of the video picture, where s is less than or equal to the number of available antennas x and greater than zero. Next, in step S530, the control circuit of the wireless transmission interface determines the antenna usage number y according to the power state of the local device, the transmission channel quality parameter, the user control signal or the feedback control signal, and performs signal processing on the video signal to generate y modulated signals are sent to the γ antennas to carry the y modulated signals to the wireless channel, where y is greater than or equal to s and less than or equal to x . In step S530, the manner of how to determine the number of antennas used by y is as described above, and will not be described herein.

In step S540, the control circuit of the wireless transmission interface is based on the signal format corresponding to the video signal, the modulation mode, the resolution of the video picture, the power status of the local device, the transmission channel quality parameter, the user control signal or the feedback control signal. control of y y connected to the antenna switch or the gain of the amplifier circuits. In addition, it is to be noted that, in step S540, the other ( xy ) amplifier circuits do not need to carry signals to the wireless channel because their corresponding ( xy ) antennas do not need to carry signals to the wireless channel, so ( xy ) amplifier circuits are turned off, that is, The transmission path corresponding to ( xy ) antennas is turned off. The gain of the y amplifier circuits corresponding to the y antennas to be transmitted with the modulation signal can be adjusted according to the above parameters, and the adjustment manner is the same as that of the foregoing FIG. 2 or FIG. 4, and the control circuit of the wireless transmission interface can be directly controlled. The gain of the amplifier circuit or the feedback variable resistor is used to adjust the gain. In addition, the wireless transmission interface can be designed in the manner as described in FIG. 3, so that the y amplifier circuits corresponding to the y antennas to carry the modulated signals have switches coupled between the input and the output, And the control circuit of the wireless transmission interface can control the short circuit and the open circuit of the switch and the open end of the y amplifier circuits according to the above parameters, and when the switch is short circuited, the corresponding amplifier circuit is turned off, and vice versa. Finally, in step S550, the wireless transmission interface uses y antennas to carry the signals it receives to the wireless channel.

Next, please refer to FIG. 6. FIG. 6 is a flowchart of a power control method for a wireless transmission interface according to another embodiment of the present invention. Compared to the method of FIG. 5, the power control method of FIG. 6 is relatively simple, and it only uses the power state of the local device to determine the switching or gain of the amplifier circuit. First, in step S610, the input interface converts the video data into a video signal, and the signal format of the video signal is a signal format corresponding to the video format of the input interface specification. Next, in step S620, the control circuit of the wireless transmission interface determines the minimum antenna usage number s according to the video format, the resolution and modulation mode of the video picture, and performs signal processing on the video signal to generate s modulated signals to s. The antenna carries the s modulated signals to the wireless channel.

Next, in step S630, the control circuit of the wireless transmission interface controls the switching or gain of the s amplifier circuits connected to the s antennas according to the power state of the local device. It is to be noted that, in step S630, the other ( x - s ) amplifier circuits do not need to carry signals to the wireless channel because their corresponding ( x - s ) antennas do not need to carry signals to the wireless channel, so ( x - s ) amplifier circuits are Off, that is, the transmission path corresponding to ( x - s ) antennas is turned off. The gain of the s amplifier circuits corresponding to the s antennas to be transmitted with the modulation signal can be adjusted according to the power supply condition, and the adjustment manner is the same as that of the foregoing FIG. 2 or FIG. 4, and the control circuit of the wireless transmission interface can directly control the amplifier. The gain of the circuit or the feedback variable is used to adjust the gain. In addition, the wireless transmission interface can be designed in the manner as described in FIG. 3, so that the s amplifier circuits corresponding to the s antennas that are to carry the modulated signal have a switch coupled between the input and the output. And the control circuit of the wireless transmission interface can control the short circuit and open circuit of the switches and switches of the s amplifier circuits according to the above parameters. When the switch is short circuited, the corresponding amplifier circuit is turned off, and vice versa. Finally, in step S640, the wireless transmission interface uses s antennas to carry the signals it receives to the wireless channel.

FIG. 7 is a flow chart of a power control method for a wireless transmission interface according to another embodiment of the present invention. The method provided in FIG. 7 is only one of the above methods, and is not intended to limit the present invention. In FIG. 7, it is assumed that the modulation method adopts 256-point QAM of OFDM, and the video format may be VGA or HDMI. When the video format is VGA, there will be 30 720×720 pixel images (720P@30fps) of video data transmitted per second; when the video format is HDMI, there will be 30 1080×1080 pixel images per second. Video data (1080P@30fps) is transmitted. In addition, the method provided by the embodiment of FIG. 7 is used for the wireless transmission interface 30 of FIG. 3, but the present invention is not limited thereto.

First, in step S710, the input interface converts the video data into a video signal, and the signal format of the video signal is a signal format corresponding to the video format of the input interface specification. Next, it is determined in step S720 that the video format is VGA or HDMI. If the video format is VGA, step S730 is performed, and the wireless transmission interface 30 determines to use two antennas 360 and 364 to transmit the video data. If the video format is HDMI, step S740 is performed, and the wireless transmission interface 30 determines to use all the antennas 360. 362, 364, 366 to transmit video data.

Next, in step S750, it is checked that the local end device is currently powered by an internal battery or an external power supply device. If the local device is currently powered by an external power supply device, in step S760, the amplifier circuit corresponding to the antenna used is turned on, and the corresponding switch is controlled to assume an open state. For example, assuming that the video format is HDMI, the amplifier circuits 340, 342, 344, and 346 are turned on in step S760, and the switches 380, 382, 384, and 386 are controlled by the control signals to assume an open state. If the local device is currently powered by the internal battery, step S770 is executed to turn off the amplifier circuit corresponding to the antenna to be used, and control the corresponding switch to assume an open state. For example, assuming that the video format is HDMI, then in step S770, amplifier circuits 340, 342, 344, and 346 are turned off, and switches 380, 382, 384, and 386 are controlled by the control signals to assume a short circuit condition. Finally, in step S780, the antenna used carries the signal it receives to the wireless channel.

Next, please refer to FIG. 8. FIG. 8 is a flowchart of a power control method for a wireless transmission interface according to another embodiment of the present invention. The method provided in FIG. 8 is only one of the above methods, and is not intended to limit the present invention. In FIG. 8, it is assumed that the modulation method adopts 256-point QAM of OFDM, and the video format may be VGA or HDMI. When the video format is VGA, there will be 30 720×720 pixel images (720P@30fps) of video data transmitted per second; when the video format is HDMI, there will be 30 1080×1080 pixel images per second. Video data (1080P@30fps) is transmitted. In addition, the method provided by the embodiment of FIG. 8 is used for the wireless transmission interface 40 of FIG. 4, but the present invention is not limited thereto.

First, in step S810, the input interface converts the video data into a video signal, and the signal format of the video signal is a signal format corresponding to the video format of the input interface specification. Next, it is determined in step S820 that the video format is VGA or HDMI. If the video format is VGA, step S830 is performed, and the wireless transmission interface 30 determines to use two antennas 460 and 464 to transmit the video data. If the video format is HDMI, step S840 is performed, and the wireless transmission interface 40 determines to use all the antennas 460. 462, 464, 466 to transmit video data.

Next, in step S850, it is checked that the local end device is currently powered by an internal battery or an external power supply device. If the local device is currently powered by an external power supply device, in step S860, the amplifier circuit corresponding to the antenna used is turned on, and the corresponding variable resistor is adjusted to increase the corresponding antenna. The gain of the amplifier circuit. For example, assuming the video format is VGA, then in step S860, amplifier circuits 440 and 444 will be turned on, and variable resistors 480 and 484 will be adjusted to increase the gain of amplifier circuits 440 and 444. If the local device is currently powered by the internal battery, in step S870, the amplifier circuit corresponding to the antenna used is turned on, and the corresponding amplifier is adjusted to reduce the amplifier corresponding to the antenna used. The gain of the circuit. For example, assuming the video format is VGA, then in step S870, amplifier circuits 440 and 444 will be turned on, and variable resistors 480 and 484 will be adjusted to reduce the gain of amplifier circuits 440 and 444. Finally, in step S880, the antenna used carries the signal it receives to the wireless channel.

The wireless transmission interface and the power control method thereof provided by the embodiments of the present invention can enable the computer or mobile device using the wireless transmission interface to transmit the video data to the remote display device, and at the same time, the wireless transmission interface is used. The number of antennas, the amplifier gain, and the amplifier's switches can be controlled by a variety of different parameters, enabling the computer or mobile device to save power, and allowing the user to watch the computer or mobile device through the remote display device. Video to enjoy high quality video.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

10. . . Video transmission system

100. . . Notebook computer

120. . . TV 120

102, 122. . . Multi-antenna transceiver

20. . . Wireless transmission interface

200, 202. . . Input interface

220. . . Transceiver chipset

240, 242, 244, 246, 248. . . Amplifier circuit

260, 262, 264, 266. . . antenna

270. . . Control circuit

30. . . Wireless transmission interface

300, 302. . . Input interface

320. . . Transceiver chipset

340, 342, 344, 346, 348. . . Amplifier circuit

360, 362, 364, 366. . . antenna

370. . . Control circuit

380, 382, 384, 386. . . switch

40. . . Wireless transmission interface

400, 402. . . Input interface

420. . . Transceiver chipset

440, 442, 444, 446, 448. . . Amplifier circuit

460, 462, 464, 466. . . antenna

470. . . Control circuit

480, 482, 484, 486. . . Variable resistance

IN1～IN3. . . Transceiver chipset input

OUT1~OUT4. . . Transceiver chip output

S510～S550. . . Step flow

S610～S640. . . Step flow

S710~S880. . . Step flow

S810～S880. . . Step flow

1 is a schematic diagram of a video transmission system provided in accordance with an embodiment of the present invention.

2 is a circuit diagram of a wireless transmission interface for transmitting video provided in accordance with an embodiment of the present invention.

3 is a circuit diagram of a wireless transmission interface provided in accordance with an embodiment of the present invention.

4 is a circuit diagram of a wireless transmission interface provided in accordance with an embodiment of the present invention.

FIG. 5 is a flow chart of a power control method for a wireless transmission interface according to an embodiment of the present invention.

6 is a flow chart of a power control method for a wireless transmission interface according to another embodiment of the present invention.

FIG. 7 is a flow chart of a power control method for a wireless transmission interface according to another embodiment of the present invention.

FIG. 8 is a flow chart of a power control method for a wireless transmission interface according to another embodiment of the present invention.

30. . . Wireless transmission interface

300, 302. . . Input interface

320. . . Transceiver chipset

340, 342, 344, 346, 348. . . Amplifier circuit

360, 362, 364, 366. . . antenna

370. . . Control circuit

380, 382, 384, 386. . . switch

IN1～IN3. . . Transceiver chipset input

OUT1~OUT4. . . Transceiver chip output

Claims (19)

A wireless transmission interface for transmitting video, comprising: an input interface for receiving a video data to be transmitted by a local device to a remote display device, and correspondingly outputting a video signal; Having an input for receiving the video signal, having x modulated signal outputs; x amplifier circuits, each amplifier circuit having an input and an output, the input of each amplifier circuit being coupled to one of the x-th output terminal of the modulation signal wherein; x antennas, each antenna coupled to one of said output ports x wherein x of the amplifier circuits; and a control circuit, to the corresponding one of the video signal Signal format, a modulation mode, a video picture resolution, a power state of the local device, a transmission channel quality parameter, a user control signal or a feedback control signal pair to control the transceiver chip set to the video signal Performing a signal processing to generate y modulated signals to the y modulated signal output terminals, and the control circuit is based on one of the signals corresponding to the video signal The format, the modulation mode, the resolution of the video screen, the power status of the local device, the quality parameter of the transmission channel, the user control signal or the feedback control signal control the output of the y modulation signal a switch of the y amplifier circuits, and transmitting the y modulated signals to a wireless channel by using the y corresponding antennas, wherein y is less than or equal to x and greater than 0, wherein the control circuit controls the corresponding signal according to the video signal The signal format, the modulation mode, and the video picture resolution determine the minimum antenna usage number s , where s is less than or equal to y . The wireless transmission interface of claim 1, wherein the control circuit is further configured according to a signal format corresponding to the video signal, the modulation mode, the resolution of the video image, the power status of the local device, The transmission channel quality parameter, the user control signal or the feedback control signal controls and controls the gain of the one or more amplifier circuits that are turned on. The wireless transmission interface of claim 1, further comprising x switches, wherein each end of each switch is coupled to an output end and an input end of each amplifier circuit, when the switch is controlled by the control circuit When a short circuit occurs, the corresponding amplifier circuit is controlled to be turned off by the control circuit, and vice versa. The wireless transmission interface of claim 1 further includes x variable resistors, wherein each end of each switch is coupled to an output end and an input end of each amplifier circuit, and the control circuit is further based on the video signal. Corresponding signal format, the modulation mode, the resolution of the video screen, the power state of the local device, the transmission channel quality parameter, the user control signal or the feedback control signal to control each variable resistor The resistance value. The wireless transmission interface of claim 1, wherein the remote display device generates the feedback control signal according to the estimated one-bit error rate or a packet loss rate, and transmits the feedback control signal Giving the wireless transmission interface, the control circuit adjusting the gain of the y amplifier circuits according to the feedback control signal, or determining the switches of the x amplifier circuits and using the y antennas to carry the y modulated signals to the Wireless channel. The wireless transmission interface of claim 1, further comprising a remote control device for transmitting the user control signal to the wireless transmission interface, the control circuit adjusting the gain of the y amplifier circuits according to the user control signal Or determining the switches of the x amplifier circuits and using the y antennas to carry the y modulated signals to the wireless channel. The wireless transmission interface of claim 1, wherein the wireless transmission interface estimates the transmission quality parameter of the channel, and the control circuit adjusts the gain of the y amplifier circuits according to the channel transmission quality parameter, or determines the x The switching of the amplifier circuits and the use of the y antennas to carry the y modulated signals to the wireless channel, wherein the channel transmission quality parameters include a one-bit error rate or a packet loss rate. The wireless transmission interface of claim 1, wherein the power status of the local device refers to the local device using an internal battery or an external power supply device, or the local device is in use. When the internal battery is powered, the internal battery is fully charged. For example, in the wireless transmission interface described in claim 8, when the local device is powered by the internal battery, the control circuit reduces the gain of the y amplifier circuits or turns off all the amplifier circuits directly. the use of the antennas y y a modulated carrier signal supplied to the wireless channel. A local device having computing capability and communication capability for transmitting a video data to a remote display device, having a wireless transmission interface, the wireless transmission interface comprising: an input interface for receiving a local device a video data to be transmitted to a remote display device, and correspondingly output a video signal; a transceiver chipset having an input for receiving the video signal, having x modulated signal outputs; x amplifiers a circuit, each of the amplifier circuits has an input end and an output end, and the input end of each of the amplifier circuits is coupled to one of the x modulated signal output ends; x antennas, each antenna coupled to the x One of the x output terminals of the amplifier circuit; and a control circuit, according to a signal format corresponding to the video signal, a modulation mode, a video picture resolution, a power state of the local device, and a Transmitting channel quality parameters, a user control signal or a feedback control signal to control the transceiver chip set to perform a signal on the video signal To generate a modulation signal y to y modulated signal output terminal, and the control circuit in accordance with a corresponding one of the signal format of the video signal, the modulation mode, the video screen resolution, the power of the local terminal device condition, the quality of the transmission channel parameter, the user of the feedback control signal or control signal y a modulated signal output y of the amplifier circuits corresponding switch, and the use of the y-antenna transmission corresponding to the number y Modulating the signal to a wireless channel, where y is less than or equal to x and greater than 0, wherein the control circuit controls the minimum antenna usage number s according to the signal format corresponding to the video signal, the modulation mode and the video image resolution, wherein s is less than or equal to y . The local device according to claim 10, wherein the control circuit is further configured according to a signal format corresponding to the video signal, the modulation mode, the resolution of the video image, the power status of the local device, The transmission channel quality parameter, the user control signal or the feedback control signal controls and controls the gain of one or more of the turned-on amplifier circuits. The local end device of claim 10, wherein the wireless transmission interface further comprises x switches, wherein each end of each switch is coupled to an output end and an input end of each amplifier circuit, when the switch is When the control circuit is controlled to be short-circuited, the correspondingly connected amplifier circuit is controlled by the control circuit to be turned off, and vice versa. The local end device of claim 10, wherein the wireless transmission interface further comprises x variable resistors, wherein each end of each switch is coupled to an output end and an input end of each amplifier circuit, the control The circuit is controlled according to the signal format corresponding to the video signal, the modulation mode, the resolution of the video picture, the power status of the local device, the transmission channel quality parameter, the user control signal or the feedback control signal The resistance value of each variable resistor. The local device according to claim 10, wherein the remote display device generates the feedback control signal according to the estimated one-bit error rate or a packet loss rate, and transmits the feedback control signal Giving the wireless transmission interface, the control circuit adjusting the gain of the y amplifier circuits according to the feedback control signal, or determining the switches of the x amplifier circuits and using the y antennas to carry the y modulated signals to the Wireless channel. The local device according to claim 10, further comprising a remote control device for transmitting the user control signal to the wireless transmission interface, the control circuit adjusting the gain of the y amplifier circuits according to the user control signal Or determining the switches of the x amplifier circuits and using the y antennas to carry the y modulated signals to the wireless channel. The local end device according to claim 10, wherein the wireless transmission interface estimates the transmission quality parameter of the channel, and the control circuit adjusts the gain of the y amplifier circuits according to the channel transmission quality parameter, or determines the x The switching of the amplifier circuits and the use of the y antennas to carry the y modulated signals to the wireless channel, wherein the channel transmission quality parameters include a one-bit error rate or a packet loss rate. The local device according to claim 10, wherein the power state of the local device refers to the local device using an internal battery or an external power supply device, or the local device is in use. When the internal battery is powered, the internal battery is fully charged. The local end device according to claim 17, wherein when the local end device is powered by the internal battery, the control circuit reduces the gain of the y amplifier circuits or turns off all the amplifier circuits, and directly uses the The y antennas carry the y modulated signals to the wireless channel. A power control method for a wireless transmission interface for transmitting a video data of a local device to a remote display device, wherein the local device has x transmission paths, each of which has a transmission path An antenna and an amplifier circuit, and the power control method includes: converting the video data into a video signal; determining a minimum antenna usage number s according to a video format of the video signal, a video picture resolution, and a modulation mode; one of said local terminal apparatus power status, channel quality parameters of a transmission, a user control signal or a feedback control signal determines the number y using the antenna, and signal processing on the video signal to generate a modulated signal y to y An antenna according to the signal format corresponding to the video signal, the modulation mode, the resolution of the video, the power status of the local device, the transmission channel quality parameter, the user control signal, or the back the feedback control signal y of the y antenna switch or the corresponding gain amplifier circuit; and using the y The antennas carry the signals they receive to a wireless channel, where y is less than or equal to x and greater than zero, and s is less than or equal to y .