Dual-channel electronic tuner and television signal receiving device

Abstract

The embodiment of the utility model provides a dual-channel electronic tuner and a television signal receiving device, which are used for solving the technical problem that the existing pre-amplified dual-channel electronic tuner cannot effectively receive stronger television signals. The dual-channel electronic tuner comprises a low noise amplifier, a signal separator, a first tuner chip and a second tuner chip. The intensity of the shunted second channel signal is detected through the second tuner chip to form a feedforward control signal, and the low-noise amplifier can adaptively adjust the processing mode of the subsequent input television signal through a control signal transmission path formed by the control port of the second tuner chip and the bypass switch of the low-noise amplifier. And high-sensitivity receiving of weak television signals and high-fidelity receiving of strong television signals are realized. Furthermore, not only is the dynamic receiving range of the dual-channel electronic tuner improved, but also stable and reliable signal receiving can be provided in environments with different signal intensities.

Description

Technical Field

[0001] The utility model embodiment relates to the technical field of signal processing, and in particular to a dual-channel electronic tuner and a television signal receiving device. Background Art

[0002] In the field of television, a dual-channel electronic tuner of a television signal receiving device has two independent television signal transmission channels. It can not only simultaneously receive and process television signals from two different channels, but also divert the television signal of the same channel into two television signal transmission channels through a signal separator. The television signal of one transmission channel is used for program viewing, and the television signal of the other transmission channel is used for program recording.

[0003] The TV signal splitting will cause about 1dB to 3dB of signal attenuation. If the received TV signal is weak, the signal attenuation caused by the signal splitting may cause mosaics to appear in the image, or even fail to output the image in extreme cases.

[0004] In order to solve this technical problem, a common practice is to enhance the input television signal through a pre-placed low noise amplifier before the signal is split.

[0005] However, in the process of implementing the technical solution in the embodiment of the utility model, the inventors found that the existing preamplifier dual-channel electronic tuner has at least the following technical problems:

[0006] If the TV signal received by the TV signal receiving device is strong, after being processed by the dual-channel electronic tuner, mosaic or no image output will occur whether it is directly displayed on the TV screen or recorded and then played back. In other words, it is impossible to effectively receive strong TV signals. Utility Model Content

[0007] In view of this, the purpose of the embodiment of the utility model is to provide a dual-channel electronic tuner and a television signal receiving device to solve the technical problem that the existing preamplified dual-channel electronic tuner cannot effectively receive strong television signals. The dual-channel electronic tuner can adaptively adjust the processing mode of the input television signal based on the strength of the shunted television signal to achieve high-sensitivity reception of weak television signals and high-fidelity reception of strong television signals.

[0008] In order to achieve the above purpose, the technical solutions adopted in the embodiments of the present invention are as follows:

[0009] In a first aspect, an embodiment of the present invention provides a dual-channel electronic tuner, which is applied to a television signal receiving device; the dual-channel electronic tuner comprises:

[0010] A low noise amplifier; the low noise amplifier comprises a gain circuit and a bypass switch; wherein the gain circuit is used to amplify the input television signal in a gain mode; the bypass switch is used to switch the working mode of the low noise amplifier between a gain mode and a bypass mode;

[0011] A signal separator, whose input end is electrically connected to the output end of the low noise amplifier, and is used to separate the television signal processed by the low noise amplifier into a first channel signal and a second channel signal;

[0012] A first tuner chip, whose input end is electrically connected to the first channel signal output end of the signal separator, is used to receive and amplify and mix the first channel signal, and output a low intermediate frequency DIF differential signal;

[0013] A second tuner chip, whose input end is electrically connected to the second channel signal output end of the signal separator, is used to receive and amplify and mix the second channel signal, and output a low intermediate frequency DIF differential signal;

[0014] The control port of the second tuner chip is electrically connected to the bypass switch of the low noise amplifier, and is used to detect and generate a feedforward control signal based on the signal strength of the second channel signal, so that the low noise amplifier can adjust the working mode based on the feedforward control signal received by the bypass switch; wherein, when the second channel signal is determined to be a weak TV signal, the low noise amplifier can enable a high gain mode for the subsequent input TV signal, and perform signal amplification processing through a gain circuit; when the second channel signal is determined to be a strong TV signal, the low noise amplifier can enable a bypass mode for the subsequent input TV signal, bypass the gain circuit, and directly transmit it to the signal separator;

[0015] The power supply unit is used to provide power to the power consumption unit of the dual-channel electronic tuner.

[0016] Optionally, the low noise amplifier is one of LTE3401L of NXP Semiconductors, QPL9095 of Qorvo, NJG1129MD7 of New Japan Radio, NJG1146KG1 of Nisshinbo Microelectronics Co., Ltd., and MGA-6x606 of Avago Technologies.

[0017] Optionally, the signal separator is one of TMUXHS4212 of Texas Instruments, BAW617 of NXP Semiconductors, and DXW21BN7511 of Murata.

[0018] Optionally, the control port of the second tuner chip is a general input and output port.

[0019] Optionally, the dual-channel electronic tuner further includes a crystal oscillator; the crystal oscillator is electrically connected to the second tuner chip and is used to provide a clock signal for the second tuner chip.

[0020] In a second aspect, an embodiment of the utility model further provides a television signal receiving device; the television signal receiving device includes the aforementioned dual-channel electronic tuner.

[0021] Based on the above technical solution, the dual-channel electronic tuner and television signal receiving device in the embodiment of the utility model, by adding the bypass switch in the low-noise amplifier, makes its working mode include gain mode and bypass mode. In the bypass mode, the input television signal can bypass the gain circuit and be directly transmitted to the signal separator; the second channel signal formed by the initial amplification and shunting in the normal gain mode is detected and evaluated by the second tuner chip, and then the feedforward control signal is generated according to the signal strength, and is transmitted to the bypass switch of the low-noise amplifier through the control port; the low-noise amplifier selects a suitable working mode to process the subsequent input television signal according to the feedforward control signal received by the bypass switch, amplifies the subsequent weak input television signal in the high gain mode, ensures that the weakest signal can be clearly received, and bypasses the gain circuit in the bypass mode for the subsequent strong input television signal to be directly transmitted to the signal separator for processing, so as to maintain the original quality of the input television signal and avoid distortion.

[0022] Compared with the existing dual-channel electronic tuner that uniformly amplifies input television signals, the dual-channel electronic tuner and television signal receiving device in the embodiment of the utility model detects the strength of the second channel signal after shunting through the second tuner chip to form the feedforward control signal, and through the control signal transmission path formed by the control port of the second tuner chip and the bypass switch of the low-noise amplifier, the low-noise amplifier can adaptively adjust the processing mode of the subsequent input television signal to achieve high-sensitivity reception of weak television signals and high-fidelity reception of strong television signals. Furthermore, not only the dynamic receiving range of the dual-channel electronic tuner is improved, but also stable and reliable signal reception can be provided under different signal strength environments, effectively solving the technical problem that the existing dual-channel electronic tuner with preamplification cannot achieve effective reception of relatively strong television signals.

[0023] Therefore, the dual-channel electronic tuner and television signal receiving device in the embodiment of the utility model can adopt appropriate signal processing strategies for complex and changeable input signals by forming a closed-loop feedback control mechanism, effectively expanding the dynamic range of signal reception. This not only improves the reception sensitivity of weak signals, but also avoids the overload distortion problem caused by strong signals, and realizes high-precision and high-quality signal reception under all working conditions. Users can obtain high-quality signals for program viewing and recording through the dual-channel electronic tuner. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic structural block diagram of a dual-channel electronic tuner in the utility model is shown;

[0026] Figure 2 A schematic structural block diagram of a dual-channel electronic tuner with a crystal oscillator in the utility model is shown;

[0027] Figure 3 The schematic structural block diagram of the television signal receiving device in the utility model is shown.

[0028] The corresponding relationship between the reference numerals and component names in the figures is as follows:

[0029] The television signal receiving device 10 includes a dual-channel electronic tuner 100 , a low noise amplifier 110 , a signal separator 120 , a first tuner chip 130 , a second tuner chip 140 , a power supply unit 150 , and a crystal oscillator 160 . DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in combination with actual application and with reference to the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0031] The dual-channel electronic tuner in the embodiment of the utility model is applied to a television signal receiving device. The television signal receiving device is a device capable of receiving radio frequency television signals, and can specifically be a television, a set-top box, a TV stick, a satellite television receiver, or a wireless television receiver.

[0032] The existing preamplifier dual-channel electronic tuner cannot achieve the technical problem of effectively receiving stronger television signals.

[0033] After in-depth research on the signal environment that existing television signal receiving devices deal with, the inventors found that the signal environment that existing television signal receiving devices deal with is complex and changeable. For the same television channel, in some areas, the television signal received by the television signal receiving device is weaker, while in other areas, the received television signal is stronger. Even in the same area, the television signal strength of different channels received by the television signal receiving device may vary significantly.

[0034] The inventors further discovered that the root cause of the technical problem of effectively receiving strong TV signals is that the existing dual-channel electronic tuner does not distinguish between the strength of the input TV signal and uniformly amplifies the input signal, resulting in strong signal overload, causing image processor decoding errors, and causing problems such as mosaics and no image output. If the strength of the input signal is evaluated before amplification, and whether to amplify the signal is determined based on the evaluation result, signal distortion can be controlled to a certain extent, and the signal reception range of the dual-channel electronic tuner can be expanded.

[0035] Based on the analysis and understanding of the root cause of the technical problem, the inventor tried to realize the automatic gain adjustment mechanism of signal strength by cooperating with the detection component of the low-noise amplifier and the limiting operation circuit. However, although this method can prevent signal overload, it often leads to insufficient amplification of weak signals when processing complex and changeable input signals. Therefore, it is difficult to take into account the processing of weak and strong signals at the same time by relying solely on the low-noise amplifier to optimize the amplification effect of the input signal.

[0036] In the process of implementing the technical solution in this practical embodiment, the inventor found that the tuner chip is used for amplification and mixing of television signals, has the function of signal strength detection and control, and the processed signal is directly used for program playback and recording. Therefore, using the tuner chip to detect the input signal and generate a strength control signal can better optimize the signal output quality.

[0037] The inventors further discovered that to ensure that weak signals are sufficiently amplified and to avoid overloading of strong signals, it is necessary to allow strong signals to bypass the gain circuit and maintain their original quality. This means that it is necessary to enable the gain mode for weak signals to be amplified, and enable the bypass mode for strong signals to bypass the gain circuit and maintain their original quality.

[0038] Based on the above understanding, the inventor provides a dual-channel electronic tuner. The tuner detects the strength of the shunted TV signal through the tuner chip, generates a feedforward control signal, and drives the bypass switch in the low-noise amplifier to dynamically adjust the working mode of the amplifier in real time. When the signal is weak, this feedforward control mechanism enables the gain mode and amplifies the signal through the gain circuit. When the signal is strong, the gain circuit is bypassed through the bypass mode, and the signal is directly transmitted backward to avoid signal overload and distortion. Furthermore, it ensures that the most appropriate processing strategy can be selected under different signal strength conditions, improves the reception sensitivity of weak signals, and avoids the overload distortion problem caused by strong signals, achieving high-precision and high-quality signal reception under all working conditions.

[0039] The technical solution of the utility model will be described below in conjunction with the accompanying drawings and embodiments.

[0040] Figure 1 The schematic structural block diagram of the dual-channel electronic tuner in the utility model is shown.

[0041] Now refer to Figure 1 As shown, in an embodiment of the utility model, a dual-channel electronic tuner is provided, which is applied to a television signal receiving device; the dual-channel electronic tuner comprises:

[0042] A low noise amplifier 110; the low noise amplifier 110 comprises a gain circuit and a bypass switch; wherein the gain circuit is used to amplify the input television signal in a gain mode; and the bypass switch is used to switch the working mode of the low noise amplifier 110 between a gain mode and a bypass mode;

[0043] A signal separator 120, whose input end is electrically connected to the output end of the low noise amplifier 110, and is used to separate the television signal processed by the low noise amplifier 110 into a first channel signal and a second channel signal;

[0044] The first tuner chip 130 has an input end electrically connected to the first channel signal output end of the signal separator 120, and is used to receive and amplify and mix the first channel signal, and output a low intermediate frequency DIF differential signal;

[0045] The second tuner chip 140 has an input end electrically connected to the second channel signal output end of the signal separator 120, and is used to receive and amplify and mix the second channel signal, and output a low intermediate frequency DIF differential signal;

[0046] The control port of the second tuner chip 140 is electrically connected to the bypass switch of the low noise amplifier 110, and is used to detect and generate a feedforward control signal based on the signal strength of the second channel signal, so that the low noise amplifier 110 can adjust the working mode based on the feedforward control signal received by the bypass switch; wherein, when the second channel signal is determined to be a weak TV signal, the low noise amplifier 110 can enable a high gain mode for the subsequent input TV signal, and perform signal amplification processing through a gain circuit; when the second channel signal is determined to be a strong TV signal, the low noise amplifier 110 can enable a bypass mode for the subsequent input TV signal, bypass the gain circuit, and directly transmit it to the signal separator 120;

[0047] The power supply unit 150 is used to provide power to the power consumption unit of the dual-channel electronic tuner.

[0048] In the embodiment of the utility model, the technical functions of realizing high-quality input TV signal processing and control are decomposed into: forming a signal processing circuit structure that allows strong TV signals to maintain their original quality, detecting and generating the feedforward control signal based on the strength of the shunted TV signal, and processing the input TV signal based on the feedforward control signal. Among them:

[0049] The sub-technical functions that form the signal processing circuit structure that allows strong TV signals to maintain their original quality are realized as follows:

[0050] The bypass switch is added to the low noise amplifier 110, so that its working mode is extended from a single gain mode to a dual working mode including a gain mode and a bypass mode. The received TV signal is initially amplified in a normal gain mode; when the TV signal formed by the shunt after the initial amplification process is judged to be a weak TV signal, the subsequent input TV signal is amplified in a high gain mode to ensure that even the weakest signal can be clearly received; when the TV signal formed by the shunt after the initial amplification process is judged to be a strong TV signal, the bypass mode is enabled for the subsequent strong input TV signal, so that the input TV signal bypasses the gain circuit and is directly transmitted to the signal separator 120 for processing, so as to maintain the original quality of the input TV signal and avoid distortion.

[0051] The sub-technical function of detecting and generating the feedforward control signal based on the strength of the shunted television signal is implemented as follows:

[0052] By utilizing the signal strength detection and control adjustment functions of the amplification and mixing processing of the second tuner chip 140, the second channel signal formed by the branching after the preliminary amplification processing is detected and evaluated, and the feedforward control signal is generated according to the signal strength.

[0053] The sub-technical function of processing the input television signal based on the feedforward control signal is realized as follows:

[0054] The control port of the second tuner chip 140 is electrically connected to the bypass switch of the low noise amplifier 110 to form the feedforward control signal transmission path. The low noise amplifier 110 switches the working mode between the gain mode and the bypass mode based on the feedforward control signal received by the bypass switch. When the feedforward control signal is a control signal corresponding to the weak TV signal after shunting, the low noise amplifier 110 enables the high gain mode, and amplifies the subsequent input TV signal through the gain circuit to significantly improve the sensitivity of the TV signal receiving device, ensuring that even the weakest signal can be clearly received; when the feedforward control signal is a control signal corresponding to the strong TV signal after shunting, the low noise amplifier 110 enables the bypass mode, and the subsequent input TV signal bypasses the gain circuit and is directly transmitted to the signal separator 120, thereby maintaining the original quality of the input TV signal and avoiding distortion.

[0055] Through the above technical means, the dual-channel electronic tuner in the embodiment of the utility model can automatically adjust the working mode of the low noise amplifier 110 based on the signal strength of one channel formed by the shunting, intelligently cope with the complex and changeable signal receiving environment, and effectively control the signal quality of the first channel signal and the second channel signal. Regardless of the strength of the external input signal, it can ensure that a high-quality, high-fidelity TV signal is obtained for program viewing and recording.

[0056] In the embodiment of the utility model, the low noise amplifier 110 includes the gain circuit and the bypass switch, and accordingly, the working mode of the low noise amplifier 110 includes a gain mode and a bypass mode. The gain circuit is used to amplify the input television signal in the gain mode; the bypass switch is used to receive the feedforward control signal to switch the working mode of the low noise amplifier 110. When the low noise amplifier 110 enables the gain mode, the subsequent input television signal is amplified by the gain circuit; when the low noise amplifier 110 enables the bypass mode, the subsequent input television signal bypasses the gain circuit and is directly transmitted to the signal separator 120.

[0057] Among them, the gain mode includes a normal gain mode and a high gain mode. The normal gain mode is used to perform preliminary amplification processing on the input TV signal; the high gain mode is used to perform high gain amplification processing on the subsequent input TV signal corresponding to the weak TV signal detected after diversion.

[0058] In an exemplary possible implementation, the low noise amplifier 110 is one of LTE3401L of NXP Semiconductors, QPL9095 of Qorvo, NJG1129MD7 of New Japan Radio, NJG1146KG1 of Nisshinbo Microelectronics Co., Ltd., and MGA-6x606 of Avago Technologies.

[0059] These low noise amplifiers include the gain circuit and the bypass switch, and have a high gain mode and a bypass mode to cover a wide dynamic range. Specifically, when the feedforward control signal is a control signal given based on a weak TV signal judgment, the low noise amplifier 110 enables the high gain mode, and the subsequent input TV signal is amplified by the gain circuit to significantly improve the sensitivity of the TV signal receiving device, ensuring that even the weakest signal can be clearly received; when the feedforward control signal is a control signal given based on a strong TV signal judgment, the low noise amplifier 110 enables the bypass mode, and the subsequent input TV signal bypasses the gain circuit and is directly transmitted to the signal separator 120, thereby maintaining the original quality of the input TV signal and avoiding distortion. By adopting this hardware circuit structure and the corresponding working mechanism, the processing mode of the subsequent input TV signal is adaptively adjusted according to the strength of the input TV signal, so as to achieve high sensitivity reception of weak TV signals and high fidelity reception of strong TV signals, improve the dynamic reception range of the dual-channel electronic tuner, and meet the needs of users when watching and recording programs.

[0060] In the embodiment of the utility model, the signal separator 120 is used to separate the television signal processed by the low noise amplifier 110 into a first channel signal and a second channel signal, and transmit the first channel signal to the first tuner chip 130, and transmit the second channel signal to the second tuner chip 140. The first channel signal and the second channel signal are processed separately, and the two do not interfere with each other, one channel signal is used to output an image from a display screen, and the other channel signal is used for program recording.

[0061] In an exemplary possible implementation, the signal separator 120 is one of TMUXHS4212 of Texas Instruments, BAW617 of NXP Semiconductors, and DXW21BN7511 of Murata.

[0062] These signal splitters are designed to accurately distribute the input signal to two channels, ensuring the integrity and stability of the signal during transmission and reducing signal attenuation caused by signal splitting.

[0063] Among them, Texas Instruments' TMUXHS4212 is a high-performance signal separator that can achieve efficient signal distribution while ensuring signal quality.

[0064] NXP Semiconductors' BAW617 is a signal separator based on bulk acoustic wave (BAW) technology that excels in high-frequency signal processing with its high frequency stability and low insertion loss characteristics.

[0065] Murata's DXW21BN7511 is suitable for space-constrained and demanding application environments with its compact design and high reliability.

[0066] During the specific implementation process, a suitable signal separator can be selected according to application requirements to meet the application scenario.

[0067] In the embodiment of the utility model, the first tuner chip 130 and the second tuner chip 140 are tuner chips commonly used in television signal receiving devices, which are used to receive and amplify and mix the shunted television signals and output low intermediate frequency DIF differential signals.

[0068] Exemplarily, in a possible implementation manner, the first tuner chip 130 and the second tuner chip 140 may specifically be the TDA18250BHN / C1 chip of NXP Semiconductors, the Si2147 chip of Silicon Labs, the M88TS2000 chip of Montage Technology, the TDA5737 chip of Philips, or the BCM43569 chip of Broadcom.

[0069] In the specific implementation process, the control port of the second tuner chip 140 is electrically connected to the bypass switch of the low noise amplifier 110 to form a closed-loop feedback control mechanism. Of course, the control port of the first tuner chip 130 can also be electrically connected to the bypass switch of the low noise amplifier 110 to form a closed-loop feedback control mechanism. In the embodiment of the utility model, the first tuner chip 130 and the second tuner chip 140 are only distinguished in name, and the functions that can be realized by the two can be consistent.

[0070] In the specific implementation process, the strength of the second channel signal after shunting can be detected by the second tuner chip 140 based on a preset weak signal threshold and a preset strong signal threshold; when the second tuner chip 140 determines that the second channel signal is a weak signal, a high level signal is output through the control port to enable the low noise amplifier 110 to start the high gain mode; when the second tuner chip determines that the second channel signal is a strong signal, a low level signal is output through the control port to enable the low noise amplifier 110 to start the bypass mode. That is, the feedforward control signal is a high level signal or a low level signal.

[0071] The control port may specifically be an I2C bus interface, a GPIO port or other types of interfaces. Among them, in a possible implementation, the GPIO port is a preferred control port.

[0072] The GPIO port is a general-purpose input and output port of the chip, which can be configured as a push-pull output mode with strong external device driving capability to achieve precise control of the switching state of the external device. This precise control is very important for applications that require precise operation.

[0073] The intelligent control mechanism based on the GPIO port can not only improve the response speed and accuracy between the second tuner chip 140 and the low noise amplifier 110, but also enhance the real-time adaptive processing of the dual-channel electronic tuner to different signal strengths. Through this flexible signal processing strategy, the dual-channel electronic tuner can maintain the best signal receiving performance in various signal environments, so that high-quality signals for program viewing and recording can be obtained through the dual-channel electronic tuner.

[0074] In the embodiment of the utility model, the reason why the second tuner chip 140 detects the strength of the second channel signal after shunting to form the feedforward control signal, rather than directly detecting the input TV signal through the low noise amplifier 110 to form the feedforward control signal, is because it is considered that the TV signal shunting will cause about 1dB to 3dB of signal attenuation. And the strength judgment of the TV signal after shunting is more conducive to high-sensitivity reception of weak TV signals and high-fidelity reception of strong TV signals.

[0075] Therefore, the second tuner chip 140 detects the strength of the second channel signal after shunting to form the feedforward control signal, which not only improves the dynamic receiving range of the dual-channel electronic tuner, but also ensures stable and reliable signal reception in different signal strength environments.

[0076] In the embodiment of the utility model, the power supply unit 150 is a power supply unit commonly used in television signal receiving devices, and is used to provide power to the power-consuming unit of the dual-channel electronic tuner.

[0077] It can be seen that in the embodiment of the utility model, the signal strength detection and control adjustment functions of the amplification and mixing processing of the second tuner chip 140 are utilized to detect and evaluate the second channel signal formed by the shunting after the initial amplification in the ordinary gain mode, and the feedforward control signal is generated based on the evaluation result, so that the low noise amplifier 110 can adaptively adjust the processing mode of the subsequent input television signal based on the feedforward control signal received by the bypass switch, so as to achieve high-sensitivity reception of weak television signals and high-fidelity reception of strong television signals.

[0078] Specifically, the low noise amplifier 110 first performs preliminary amplification processing on the received TV signal in the normal gain mode; then, the signal separator 120 divides the signal after preliminary amplification processing into a first channel signal and a second channel signal and transmits them to the first tuner chip 130 and the second tuner chip 140 respectively; the second tuner chip 140 uses its signal strength detection and evaluation capabilities to evaluate the strength of the TV signal after diversion and generate the corresponding feedforward control signal, and transmits it to the bypass switch of the low noise amplifier 110 through the control port. The low noise amplifier 110 switches the working mode between the gain mode and the bypass mode based on the received feedforward control signal. When the feedforward control signal is a control signal corresponding to the weak TV signal after shunting, the low-noise amplifier 110 enables a high-gain mode, and amplifies the subsequent input TV signal through the gain circuit to significantly improve the sensitivity of the TV signal receiving device, ensuring that even the weakest signal can be clearly received; on the contrary, when the feedforward control signal is a control signal corresponding to the strong TV signal after shunting, the low-noise amplifier 110 enables a bypass mode, and the subsequent input TV signal bypasses the gain circuit and is directly transmitted to the signal separator 120 to prevent signal overload and distortion and maintain the original quality of the signal.

[0079] Through this closed-loop feedback control mechanism, the dual-channel electronic tuner can dynamically and adaptively adjust the working mode of the low-noise amplifier 110 according to the signal strength after shunting, and intelligently cope with complex and changeable signal receiving environments. Whether in the case of weak signals or strong signals, appropriate signal processing strategies can be adopted to ensure wide range, high reliability and stability of signal reception in different signal strength environments.

[0080] Compared with the existing dual-channel electronic tuner that uniformly amplifies input television signals, the dual-channel electronic tuner and television signal receiving device in the embodiment of the utility model detects the strength of the second channel signal after shunting through the second tuner chip 140 to form the feedforward control signal, and through the control signal transmission path formed by the control port of the second tuner chip 140 and the bypass switch of the low-noise amplifier 110, the low-noise amplifier 110 can adaptively adjust the processing mode of the subsequent input television signal to achieve high-sensitivity reception of weak television signals and high-fidelity reception of strong television signals. Furthermore, not only the dynamic receiving range of the dual-channel electronic tuner is improved, but also stable and reliable signal reception can be provided under different signal strength environments, effectively solving the technical problem that the existing pre-amplified dual-channel electronic tuner cannot achieve effective reception of relatively strong television signals.

[0081] Therefore, the dual-channel electronic tuner and television signal receiving device in the embodiment of the utility model can adopt appropriate signal processing strategies for complex and changeable input signals by forming a closed-loop feedback control mechanism, effectively expanding the dynamic range of signal reception. This not only improves the reception sensitivity of weak signals, but also avoids the overload distortion problem caused by strong signals, and realizes high-precision and high-quality signal reception under all working conditions. Users can obtain high-quality signals for program viewing and recording through the dual-channel electronic tuner.

[0082] For circuit structures that adopt closed-loop feedback control mechanism, clock signal is the basis of synchronous circuit operation.

[0083] Figure 2 The schematic structural block diagram of the dual-channel electronic tuner with crystal oscillator in the utility model is shown.

[0084] Now refer to Figure 2 As shown, in a possible implementation manner, the dual-channel electronic tuner further includes a crystal oscillator 160 ; the crystal oscillator 160 is electrically connected to the second tuner chip 140 to provide a clock signal for the second tuner chip 140 .

[0085] In the embodiment of the utility model, the crystal oscillator 160 is a crystal oscillator commonly used in television signal receiving devices. The crystal oscillator 160 is electrically connected to the second tuner chip 140 to provide an accurate clock signal for the second tuner chip 140. The clock signal provided by the crystal oscillator 160 is the basis for the operation of the synchronization circuit, ensuring the accuracy of the second channel signal strength sampling and the accuracy of the generated feedforward control signal, while also ensuring that the feedforward control signal can be transmitted to the bypass switch of the low noise amplifier 110 in real time.

[0086] Figure 3 The schematic structural block diagram of the television signal receiving device in the utility model is shown.

[0087] Now refer to Figure 3 As shown, the embodiment of the utility model further provides a television signal receiving device 10 ; the television signal receiving device 10 includes the aforementioned dual-channel electronic tuner 100 .

[0088] In the embodiment of the utility model, the television signal receiving device 10 is a device capable of receiving radio frequency television signals, and specifically can be a television, a set-top box, a TV stick, a satellite television receiver, or a wireless television receiver.

[0089] It should be understood that the dual-channel electronic tuner 100 in the embodiment of the television signal receiving device of the present invention is the dual-channel electronic tuner in the aforementioned embodiment of the dual-channel electronic tuner of the present invention. For the convenience and simplicity of description, the description of the dual-channel electronic tuner in the embodiment of the television signal receiving device of the present invention can refer to the relevant description in the embodiment of the dual-channel electronic tuner, and will not be repeated here.

Claims

1. A dual-channel electronic tuner, used in a television signal receiving device; characterized in that: The dual-channel electronic tuner comprises: A low noise amplifier; the low noise amplifier comprises a gain circuit and a bypass switch; wherein the gain circuit is used to amplify the input television signal in a gain mode; the bypass switch is used to switch the working mode of the low noise amplifier between a gain mode and a bypass mode; A signal separator, whose input end is electrically connected to the output end of the low noise amplifier, and is used to separate the television signal processed by the low noise amplifier into a first channel signal and a second channel signal; A first tuner chip, whose input end is electrically connected to the first channel signal output end of the signal separator, is used to receive and amplify and mix the first channel signal, and output a low intermediate frequency DIF differential signal; A second tuner chip, whose input end is electrically connected to the second channel signal output end of the signal separator, is used to receive and amplify and mix the second channel signal, and output a low intermediate frequency DIF differential signal; The control port of the second tuner chip is electrically connected to the bypass switch of the low noise amplifier, and is used to detect and generate a feedforward control signal based on the signal strength of the second channel signal, so that the low noise amplifier can adjust the working mode based on the feedforward control signal received by the bypass switch; wherein, when the second channel signal is determined to be a weak TV signal, the low noise amplifier can enable a high gain mode for the subsequent input TV signal, and perform signal amplification processing through a gain circuit; when the second channel signal is determined to be a strong TV signal, the low noise amplifier can enable a bypass mode for the subsequent input TV signal, bypass the gain circuit, and directly transmit it to the signal separator; The power supply unit is used to provide power to the power consumption unit of the dual-channel electronic tuner.

2. The dual-channel electronic tuner according to claim 1, characterized in that: The low noise amplifier is one of LTE3401L of NXP Semiconductors, QPL9095 of Qorvo, NJG1129MD7 of New Japan Radio, NJG1146KG1 of Nisshinbo Microelectronics Co., Ltd., and MGA-6x606 of Avago Technologies.

3. The dual-channel electronic tuner according to claim 1, characterized in that: The signal separator is one of TMUXHS4212 of Texas Instruments, BAW617 of NXP Semiconductors, and DXW21BN7511 of Murata.

4. The dual-channel electronic tuner according to any one of claims 1 to 3, characterized in that: The control port of the second tuner chip is a general input and output port.

5. The dual-channel electronic tuner according to any one of claims 1 to 3, characterized in that: The dual-channel electronic tuner further includes a crystal oscillator; the crystal oscillator is electrically connected to the second tuner chip and is used to provide a clock signal for the second tuner chip.

6. A television signal receiving device; characterized in that: The television signal receiving device comprises the dual-channel electronic tuner according to any one of claims 1-5.

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