An adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit and its application

Abstract

The present invention discloses an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit and its application. The circuit can select the TV program signal of the corresponding satellite according to the different satellites received, and output the product attitude related information for use by the installer. The local oscillator is selected by pulling the mechanical three-stage switch, and then the frequency band, polarization and satellite are switched through the 0KHz / 22KHz signal and the 14V / 16V switching voltage circuit. In addition, a three-axis azimuth sensing circuit and an MCU circuit connected thereto are provided to facilitate the installer to obtain the product's rotation degree, azimuth, elevation angle and other information. This new circuit can not only meet the needs of the global satellite TV market, but also greatly reduce the working time and intensity of outdoor installers in harsh environments such as high temperature, low temperature and high cold by adding low-cost circuits such as three-axis azimuth sensing, thereby reducing installation costs.

Description

[Technical field]

[0001] The invention relates to a low-noise frequency reducer for receiving satellite TV signals, in particular to an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise frequency reducer. [Background technology]

[0002] Existing low noise downconverters (LNBs) can usually only receive satellite signals within a specific frequency range, and the installation and debugging process is complicated, requiring a lot of time and human resources. Especially in hot or cold environments, the work intensity of installers is high and there is a certain degree of danger. Therefore, it is of great practical significance to develop an LNB that can adapt to different satellite frequency bands and is easy to install and debug. [Summary of the invention]

[0003] To solve the above problems, an adjustable multi-local oscillator intelligent single-output KU-band low-noise downconverter is proposed, which can select different local oscillators according to the reception of different satellites, output the TV program signals of the corresponding satellites, and output product attitude related information at the same time.

[0004] An adjustable multi-local oscillator intelligent single-output KU band low-noise downconverter circuit and its application, characterized by comprising a first-stage satellite signal amplifier, a single-output CMOS satellite tuner, a reference frequency crystal oscillator, a local oscillator selection circuit, a signal amplification circuit, a three-axis azimuth sensing circuit, a power supply circuit and an MCU circuit as well as input and output terminals.

[0005] The output end of the first stage satellite signal amplifier is connected to a single output CMOS satellite tuner through a capacitor, and the tuner is connected to the output ends of the two first stage amplifiers through a capacitor to receive the amplified vertical and horizontal polarization signals.

[0006] The reference frequency crystal oscillator is 25 MHz, which provides a reference frequency for the local oscillator signal of the single-output CMOS satellite tuner.

[0007] The local oscillator selection circuit selects different local oscillator frequencies by pulling out a mechanical three-stage switch. The local oscillator selection circuit switches the frequency band, polarization and satellite through a 0KHz / 22KHz signal and a 14V / 16V switching voltage circuit.

[0008] The signal amplification circuit includes an RX filter amplification circuit and a TX signal amplification circuit.

[0009] The three-axis orientation sensing circuit generates a control signal related to the orientation of the satellite antenna. The three-axis orientation sensing circuit is connected to the MCU circuit. The integration of the three-axis orientation sensing circuit and the MCU circuit can provide the product's rotation, orientation and elevation information.

[0010] The power supply circuit includes a 6V power supply circuit and a 3.3V power supply circuit. The working voltage of the single-output CMOS satellite tuner is provided by the 6V power supply circuit. The working voltage of the three-axis azimuth sensing circuit and the MCU circuit is provided by the 3.3V power supply circuit. The working voltage of the signal amplification circuit is provided by the 3.3V power supply circuit and the input end.

[0011] The working steps of the downconverter circuit are as follows:

[0012] 1) Signal reception and amplification: The satellite signal is amplified by the first-stage satellite signal amplifier and then tuned by a single-output CMOS satellite tuner.

[0013] 2) Local oscillator selection: Use a mechanical three-stage switch to select different local oscillator frequencies to receive signals from different satellites.

[0014] 3) Signal filtering and amplification: The RX signal filtering and amplification circuit filters and amplifies the received signal, and then passes it to the MCU.

[0015] 4) Three-axis orientation sensing: The MCU activates the three-axis orientation sensing circuit based on the received signal to collect the product’s attitude information.

[0016] 5) Information feedback: The posture information is sent back to the set-top box through the TX signal amplification circuit, and the installer assists in the installation through the installation APP on the set-top box or the installation APP on the smartphone connected to the set-top box network.

[0017] Furthermore, the first-stage satellite signal amplifier includes a satellite vertical polarization signal amplifier and a satellite horizontal polarization signal amplifier, and the bias voltage of the satellite vertical polarization signal amplifier is provided by a single-output CMOS satellite tuner.

[0018] The output ends of the satellite vertical polarization signal amplifier and the satellite horizontal polarization signal amplifier are respectively connected to the single-output CMOS satellite tuner through capacitor conduction to form a closed-loop system.

[0019] The bias voltage is adjusted by the detected STB signal and the 14V / 16V switching voltage to adapt to different working conditions and requirements. The STB signal is a 0KHz / 22KHz signal. The switching voltage is provided by the set-top box. 14V represents vertical polarization and 16V represents horizontal polarization.

[0020] Furthermore, the TX signal amplification circuit is composed of two stages of transistors. The main function of the TX signal amplification circuit is to power amplify the transmitted signal. Each transistor is responsible for amplifying a specific frequency range. The first-stage transistor is used for primary signal amplification, amplifying the input signal to a suitable level for processing by the next-stage amplifier. The second-stage transistor further amplifies the signal transmitted from the first stage; the signal enters the first-stage transistor amplifier, is transmitted to the second-stage transistor amplifier after amplification, and then is output from the second-stage amplifier and is ready to be transmitted to the next circuit module or transmitting antenna. This design can improve the stability and reliability of the signal.

[0021] Furthermore, the RX signal filtering and amplifying circuit is located at the input end of the system and is responsible for filtering and amplifying the control signal transmitted from the set-top box. Specifically, one end is connected to the output end, amplifying the received signal to increase the level of the received signal for subsequent signal processing. The other end is electrically connected to the MCU circuit to pass the amplified signal to the MCU for further processing.

[0022] The RX signal filtering and amplifying circuit filters and amplifies the control signal generated by the three-axis orientation sensing circuit of the set-top box. This step ensures that the quality and strength of the signal are effectively guaranteed during the signal transmission process from the three-axis orientation sensing circuit to the MCU circuit, thereby improving the performance and reliability of the overall system.

[0023] Furthermore, the MCU circuit uses the PMS171B-S08 MCU to process the signal from the RX signal amplification circuit and perform corresponding control operations. It has a 96-byte data memory for storing temporary data and variables, and a peripheral interface to connect other peripheral devices, such as sensors, display screens, etc., for data exchange and control.

[0024] Furthermore, the three-axis orientation sensing circuit uses an ultra-low power high-performance three-axis acceleration sensor LIS2DH12TR, whose embedded FIFO is used to store data, which can reduce the processing burden of the MCU. This sensor can measure acceleration in three axes and is often used in applications such as motion detection and gesture recognition. It can provide accurate three-axis acceleration measurement, and its ultra-low power consumption makes it very suitable for portable devices and battery-powered application scenarios.

[0025] Furthermore, an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit and application, the application method is:

[0026] Select satellite: Users select the satellite name through the APP, and the APP will recommend a suitable local oscillator frequency based on the location and satellite parameters.

[0027] LO selection: The user or system selects the appropriate LO frequency through a three-position switch. Each switch position corresponds to a LO frequency. The three-position switch is used to select three different states. In the LO selection circuit, three different LO frequencies can be selected.

[0028] Signal reception and processing: After selecting the appropriate local oscillator frequency, the LNB can receive and process the signal from the satellite, convert it into an intermediate frequency signal and transmit it to the receiver.

[0029] Azimuth sensing and adjustment: Sensors such as LIS2DH12TR are used to detect the azimuth and angle of the antenna. The APP guides users to adjust the antenna based on this data to obtain the best signal.

[0030] The adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit of the present invention can realize multiple frequency selections through different switch combinations to adapt to different application requirements. Compared with using multiple independent circuits to realize different frequencies, this design realizes frequency selection through switch combination, simplifies circuit design, and reduces the number of components. This adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit not only improves the performance of satellite TV signal reception, but also significantly reduces the installation difficulty and cost, and has important market and practical application value.

Brief Description of the Drawings

[0031] Figure 1 This is a product circuit architecture diagram of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit of the present invention;

[0032] Figure 2 The invention discloses an RX signal filtering and amplifying circuit of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise frequency reducer circuit;

[0033] Figure 3 The invention discloses a TX signal amplifying circuit of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise frequency downconverter circuit.

[0034] Figure 4 The present invention is an MCU circuit of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit.

[0035] Figure 5 The invention discloses a three-axis azimuth sensing circuit of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise frequency reducer circuit.

[0036] Figure 6 The invention discloses a multi-local oscillator switching circuit of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise frequency reducer circuit.

[0037] Figure 7 This is a process control diagram of an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter according to the present invention. [Specific implementation method]

[0038] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0039] like Figure 1-7 As shown, an adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit comprises a first-stage satellite signal amplifier (0), a single-output CMOS satellite tuner (3), a reference frequency crystal oscillator (4), the reference frequency crystal oscillator is 25MHz, and provides a reference frequency for the local oscillator signal of the single-output CMOS satellite tuner (3). A 6V power supply circuit (8), a local oscillator selection circuit (5), a 3.3V power supply circuit (9), an RX signal filtering and amplifying circuit (7), a TX signal amplifying circuit (6), a three-axis azimuth sensing circuit (11) and an MCU circuit (10) connected thereto, and an output terminal (12).

[0040] The first-stage satellite signal amplifier includes a satellite vertical polarization signal amplifier (1) and a satellite horizontal polarization signal amplifier (2). The satellite vertical polarization signal amplifier (1) amplifies the satellite vertical polarization signal; the satellite horizontal polarization signal amplifier (2) amplifies the satellite horizontal polarization signal. The output ends of the satellite vertical polarization signal amplifier (1) and the satellite horizontal polarization signal amplifier (2) are respectively connected to a single-output CMOS satellite tuner (3) through capacitor conduction to form a closed-loop system. The bias voltage of the satellite vertical polarization signal amplifier (1) is determined by the single-output CMOS satellite tuner (3) and the STB signal detected by the 0KHz / 22KHz signal and the 14V / 16V switching voltage circuit, and then part of the circuit is powered accordingly according to the voltage provided by the STB signal. Among them, the switching voltage is provided by the set-top box, 14V represents vertical polarization, 16V represents horizontal polarization, the working voltage of the single-output CMOS satellite tuner is provided by the 6V power supply circuit (8), the working voltage of the three-axis azimuth sensing circuit and the MCU circuit is provided by the 3.3V power supply circuit, and the working voltage of the signal amplification circuit is provided by the 3.3V power supply circuit and the input end. The purpose of this design is to receive and process signals from satellites, improve the reception quality of signals through different polarization modes (vertical and horizontal), and achieve stable signal processing and transmission through the tuner and power supply circuit. The local oscillator selection circuit (5) adopts a selection circuit composed of three-stage switches, each switch position corresponds to a local oscillator frequency, and different local oscillator frequencies are selected by pulling the mechanical three-stage switch. The downconverter LNB can switch between low frequency, medium frequency and high frequency to receive different satellite signals.

[0041] The TX signal amplifier circuit (6) is composed of two stages of triodes. The first stage triode amplifies the primary signal and amplifies the input signal to a suitable level for processing by the next stage amplifier. The second stage triode further amplifies the signal from the first stage to ensure that the signal reaches the required transmission strength. The signal enters the first stage triode amplifier, is amplified and transmitted to the second stage triode amplifier, and then output from the second stage amplifier and is ready to be transmitted to the next circuit module or transmitting antenna. In practical applications, the TX signal amplifier circuit needs to operate accurately at a predetermined frequency and gain setting. To achieve this, the design and manufacturing process of the circuit needs to be highly precise, so each triode is responsible for amplifying a specific frequency range to ensure that the accuracy and stability of the circuit meet the expected requirements.

[0042] One end of the RX signal filter amplifier circuit (7) is electrically connected to the output end (12) to amplify the received signal and increase the level of the received signal; the other end is electrically connected to the MCU circuit (10) to finally receive the processed signal and perform corresponding control and operation. This circuit is responsible for filtering and amplifying the signal from the set-top box. The RX signal filter amplifier circuit (7) removes unnecessary noise and interference through filtering to ensure the purity of the signal. The amplification process enhances the signal strength so that it can be effectively processed by subsequent circuits. The specific working process is as follows:

[0043] 1) The three-axis orientation sensing circuit (11) generates control signals related to the orientation of the satellite antenna, and the set-top box receives and sends these control signals.

[0044] 2) The RX signal amplifying circuit (7) receives the control signal from the set-top box, and performs filtering and amplification processing on it.

[0045] 3) The MCU circuit (10) finally receives the processed signal and performs corresponding control and operation.

[0046] This design ensures that the quality and strength of the signal are effectively guaranteed during the signal transmission process from the three-axis orientation sensing circuit to the MCU circuit, thereby improving the performance and reliability of the overall system.

[0047] The MCU circuit (10) uses a PMS171B-S08 with a 96-byte data memory, which is responsible for processing the signal from the RX signal filter amplifier circuit (7) and performing corresponding control operations. Its peripheral interface is connected to other peripheral devices, such as sensors, display screens, etc., for data exchange and control. During operation, the RX signal filter amplifier circuit (7) receives and amplifies the signal, and the MCU circuit (10) processes the received signal and performs corresponding operations according to the processing result. Then the TX signal amplifier circuit (6) amplifies the processed signal and sends it out.

[0048] The three-axis orientation sensing circuit (11) uses an ultra-low power high-performance three-axis acceleration sensor LIS2DH12TR. It has an embedded FIFO for storing data, which can reduce the processing burden of the MCU. At the same time, this sensor can measure the acceleration in the three-axis direction and is often used in applications such as motion detection and posture recognition. Its ultra-low power consumption makes it very suitable for portable devices and battery-powered application scenarios.

[0049] as follows Figure 7As shown, when the present invention is used, the user selects the satellite name through the APP, and the APP recommends a suitable local oscillator frequency according to the location and satellite parameters. The user or system selects a suitable local oscillator frequency through a three-stage switch, and each switch position corresponds to a local oscillator frequency. After selecting a suitable local oscillator frequency, the LNB can receive and process the signal from the satellite, convert it into an intermediate frequency signal and transmit it to the receiver. Sensors such as LIS2DH12TR detect the azimuth and angle of the antenna. The APP guides the user to adjust the antenna based on these data to obtain the best signal. The following are the steps for using the downconverter LNB and antenna installation APP:

[0050] Select satellite name: First select the satellite name you want to receive TV signals in the APP.

[0051] Select antenna information: Then select the manufacturer and model of the butterfly antenna.

[0052] Get GPS location: The APP will calculate the antenna installation parameters based on the detected GPS location.

[0053] Calculate installation parameters: Based on the GPS position, the APP will automatically calculate the antenna elevation, azimuth and rotation of the downconverter.

[0054] Install the antenna: The installer installs the antenna according to the elevation angle, azimuth angle and downconverter rotation degree provided by the APP.

[0055] Real-time data feedback: The three-axis position sensing circuit will transmit data back in real time, and the installer can see the real-time installation status in the APP.

[0056] Check installation correctness: When the installer sees two green "OK" characters in the APP, the installation is complete.

[0057] Confirm signal quality: After the installation is complete, the installer can see the green word "FINE" in the APP, which means that the satellite TV signal is very good.

[0058] The above description is only a preferred embodiment of the invention and is not intended to limit the invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the invention should be included in the protection scope of the invention.

Claims

1. An adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit, characterized in that: The adjustable multi-local oscillator intelligent single-output KU band low-noise frequency downconverter circuit includes a first-stage satellite signal amplifier, a single-output CMOS satellite tuner, a reference frequency crystal oscillator, a local oscillator selection circuit, a signal amplification circuit, a three-axis azimuth sensing circuit, a power supply circuit and an MCU circuit. The output ends of the first-stage satellite signal amplifier are respectively connected to the single-output CMOS satellite tuner through capacitor conduction, the reference frequency crystal oscillator is 25MHz, and provides a reference frequency for the local oscillator signal of the single-output CMOS satellite tuner. The local oscillator selection circuit selects different local oscillator frequencies by pulling out a mechanical three-stage switch; the first-stage satellite signal amplifier includes a satellite vertical polarization signal amplifier and a satellite horizontal polarization signal amplifier, the bias voltage of the satellite vertical polarization signal amplifier is provided by the single-output CMOS satellite tuner, the bias voltage is adjusted by the detected STB signal and 14V and 16V switching voltages, 14V represents vertical polarization, 16V represents horizontal polarization, the switching voltage is provided by a set-top box, and the STB signal includes a 0KHz / 22KHz signal; The signal amplification circuit includes an RX signal filtering and amplification circuit and a TX signal amplification circuit. The TX signal amplification circuit is composed of two stages of triodes, each of which is responsible for amplifying a specific frequency range. The first stage triode is responsible for preliminarily amplifying the input signal and improving the signal level. The second stage triode further amplifies the amplified signal to ensure that the signal is strong enough for effective transmission. The RX signal filtering and amplification circuit filters and amplifies the control signal generated by the three-axis azimuth sensing circuit. One end of the RX signal filtering and amplification circuit is connected to the output end to amplify the received signal and improve the level of the received signal. The other end is electrically connected to the MCU circuit. The three-axis orientation sensing circuit is connected to the MCU circuit, and the three-axis orientation sensing circuit generates a control signal related to the orientation of the satellite antenna. The three-axis orientation sensing circuit adopts the ultra-low power consumption and high-performance three-axis acceleration sensor LIS2DH12TR; the MCU circuit uses the PMS171B-S08 MCU to process the signal from the RX signal amplification circuit and perform corresponding control operations; The power supply circuit includes a 6V power supply circuit and a 3.3V power supply circuit. The working voltage of the single-output CMOS satellite tuner is provided by the 6V power supply circuit. The working voltage of the three-axis orientation sensing circuit and the MCU circuit is provided by the 3.3V power supply circuit. The working voltage of the signal amplification circuit is provided by the 3.3V power supply circuit and the input end. The working steps of the downconverter are: 1) Signal reception and amplification: The satellite signal is amplified by the first-stage satellite signal amplifier and then tuned by a single-output CMOS satellite tuner. 2) Local oscillator selection: Use a mechanical three-stage switch to select different local oscillator frequencies to receive signals from different satellites. 3) Signal filtering and amplification: The RX signal filtering and amplification circuit filters and amplifies the received signal, and then passes it to the MCU. 4) Three-axis orientation sensing: The MCU activates the three-axis orientation sensing circuit based on the received signal to collect the product’s attitude information. 5) Information feedback: The posture information is sent back to the set-top box through the TX signal amplification circuit, and the installer assists in the installation through the installation APP on the set-top box or the installation APP on the smartphone connected to the set-top box network.

2. The adjustable multi-local oscillator intelligent single-output KU frequency band low noise downconverter circuit according to claim 1, characterized in that: The application method of the adjustable multi-local oscillator intelligent single-output KU frequency band low-noise downconverter circuit is as follows: 1) The user selects the satellite name through the APP, and the APP will recommend the appropriate local oscillator frequency based on the location and satellite parameters. 2) The user or system selects the appropriate local oscillator frequency through a three-position switch. Each switch position corresponds to a local oscillator frequency. 3) After selecting the appropriate local oscillator frequency, the downconverter can receive and process the signal from the satellite, convert it into an intermediate frequency signal and transmit it to the receiver. 4) The LIS2DH12TR sensor detects the antenna’s position and angle, and the APP guides the user to adjust the antenna based on this data to obtain the best signal.

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