Automatic Tuning Wideband Radio Frequency Communication Control Device, Method and System

Abstract

The present invention relates to an automatic tuning broadband radio frequency communication control device, method and system. The automatic tuning broadband radio frequency communication control device includes a preamplifier, a frequency control unit and a feedback unit. The preamplifier includes at least one amplifier with adjustable frequency and at least one amplifier load connected to each amplifier. The frequency band of the preamplifier covers multiple channels required for the operation of the communication system. The frequency control unit includes a voltage-controlled oscillator and a self-calibration module. The self-calibration module calibrates the local oscillator output from the voltage-controlled oscillator to the mixer based on the current channel of the communication system and forms a control instruction associated with the calibrated local oscillator. The feedback unit synchronously outputs the control instruction generated by the self-calibration module to each amplifier load in the preamplifier. Each amplifier load adjusts its load parameters based on the control instruction to adjust the frequency of each amplifier so that the preamplifier has the same or associated operating frequency as the voltage-controlled oscillator.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication, and particularly to an automatic tuning broadband radio frequency communication control device, method and system. Background Art

[0002] With the development of communication technology, high-frequency and broadband application technology solutions have become increasingly important. Broadband communication methods such as WIFI6, 5G communication, and UWB have entered people's lives. However, with the increase in frequency and bandwidth, the requirements for communication circuits are getting higher and higher. Traditional narrowband technology solutions have become increasingly unable to meet the requirements of communication systems. The arrival of broadband systems poses a huge challenge to design. While obtaining high frequency and large bandwidth, it is also necessary to meet requirements such as system noise and out-of-band rejection. To achieve good noise and out-of-band rejection, it is necessary to narrow the bandwidth as much as possible during application. This pair of contradictory problems has a greater impact on the performance of the system due to the structural characteristics and non-adjustability of the circuit itself in traditional broadband solutions; especially in the presence of interference signals, due to the undifferentiated amplification of broadband circuits, that is, the system amplifies signals within the current channel and signals outside the current channel synchronously, thus greatly deteriorating the noise and out-of-band rejection performance of the system.

[0003] In addition, compared with traditional narrowband amplifiers, broadband amplifiers are more difficult to implement in circuits. Firstly, broadband matching requires a large area; secondly, the current consumed by broadband circuits is huge, and a very long time is often required to optimize the design in order to obtain good technical performance. Obviously, this high optimization cost and large chip area are often unacceptable in the field of high-performance and low-cost integrated circuits. Summary of the Invention

[0004] In order to overcome at least one deficiency of the prior art, the present invention provides an automatic tuning broadband radio frequency communication control device, method and system that obtain narrowband-like characteristics in a broadband communication system.

[0005] To achieve the above object, the present invention provides an automatic tuning broadband radio frequency communication control device, which includes a preamplifier, a frequency control unit, and a feedback unit. The preamplifier includes at least one frequency tunable amplifier and at least one amplifier load connected to each amplifier. The frequency band of the preamplifier covers multiple channels required for the operation of the communication system. The frequency control unit includes a voltage controlled oscillator and a self-calibration module. The self-calibration module calibrates the local oscillator output from the voltage controlled oscillator to the mixer based on the current channel of the communication system, and forms a control instruction associated with the calibrated local oscillator. The feedback unit synchronously outputs the control instruction generated by the self-calibration module to each amplifier load in the preamplifier. Each amplifier load adjusts its load parameters based on the control instruction, and adjusts the frequency of each amplifier so that the preamplifier has the same or associated operating frequency as the voltage controlled oscillator. The preamplifier amplifies the signal in the current channel of the communication system and suppresses the signals outside the current channel.

[0006] According to an embodiment of the present invention, the amplifier load is an LC load or a resistive feedback load; when the amplifier load is an LC load, the control instruction is the value of the calibration control word of the capacitor array in the voltage controlled oscillator. The LC load in the preamplifier adjusts the configuration of its capacitor array based on the value of the calibration control word of the capacitor array, and changes the frequency of the amplifier connected to the LC load; the value of the calibration control word is the value of the control word of the capacitor array when the voltage controlled oscillator outputs with the calibrated local oscillator.

[0007] According to an embodiment of the present invention, the preamplifier includes two cascaded band-pass amplifiers and two LC loads respectively connected to the two band-pass amplifiers.

[0008] According to an embodiment of the present invention, the preamplifier includes two cascaded amplifiers, one of which is a low-pass amplifier and the amplifier load connected to it is a resistive feedback load; the other is a band-pass amplifier and the amplifier load connected to it is an LC load.

[0009] According to an embodiment of the present invention, the maximum gain values of the two amplifiers are equal. Based on the control instruction output by the frequency control unit, each amplifier load adjusts the frequency and roll-off coefficient of the amplifier connected to it, and a current channel of the communication system is formed between the inflection point frequency of the low-pass amplifier and the center frequency of the band-pass amplifier, and each frequency point in this frequency range has an equal or approximate gain.

[0010] According to an embodiment of the present invention, the automatic tuning broadband radio frequency communication control device further includes a power detection circuit. The power detection circuit is connected to the output of the mixer in the communication system, detects the output power or amplitude of the mixer and feeds it back to the preamplifier.

[0011] On the other hand, the present invention also provides an automatic tuning broadband radio frequency communication control method, which includes:

[0012] Based on the current channel of the communication system, calibrate the local oscillator output from the voltage-controlled oscillator to the mixer, and form a control command associated with the calibrated local oscillator;

[0013] Synchronously output the control commands generated by the self-calibration module to each amplifier load in the preamplifier. The preamplifier includes at least one frequency-tunable amplifier and at least one amplifier load connected to each amplifier. The frequency band of the preamplifier covers multiple channels required for the operation of the communication system;

[0014] Each amplifier load adjusts its load parameters based on the control command, and adjusts the frequency of each amplifier so that the preamplifier has the same or associated operating frequency as the voltage-controlled oscillator. The preamplifier amplifies the signals in the current channel of the communication system and suppresses the signals outside the current channel.

[0015] According to an embodiment of the present invention, when the amplifier load is an LC load, the control command is the value of the calibration control word of the capacitor array in the voltage-controlled oscillator. The LC load in the preamplifier adjusts the configuration of its capacitor array based on the value of the calibration control word of the capacitor array, and changes the frequency of the amplifier connected to the LC load; the value of the calibration control word is the value of the control word of the capacitor array when the voltage-controlled oscillator outputs with the calibrated local oscillator.

[0016] According to an embodiment of the present invention, the preamplifier includes two cascaded amplifiers with equal maximum gain values, one of which is a low-pass amplifier and the other is a band-pass amplifier; the automatic tuning broadband radio frequency communication control method further includes: based on the control command output by the frequency control unit, each amplifier load adjusts the roll-off coefficient of the amplifier connected to it, and a communication system current channel is formed between the inflection point frequency of the low-pass amplifier and the center frequency of the band-pass amplifier, and each frequency point in this frequency range has equal or nearly equal gain.

[0017] On the other hand, the present invention also provides an automatic tuning broadband radio frequency communication system, which includes the above-mentioned automatic tuning broadband radio frequency communication control device and a mixer. The output of the preamplifier in the automatic tuning broadband radio frequency communication control device and the frequency control unit are respectively connected to the input of the mixer.

[0018] In summary, in the automatic tuning broadband radio frequency communication control device, method and system provided by the present invention, the amplifiers located in the pre-amplifier are all frequency-tunable structures, and the frequency band of the pre-amplifier covers multiple channels required for the operation of the communication system, that is, the pre-amplifier has broadband characteristics. The frequency control unit forms corresponding control instructions when calibrating the local oscillator output by the voltage-controlled oscillator based on the current channel of the communication system and synchronously outputs the control instructions to each amplifier load in the pre-amplifier. Each amplifier load adjusts its parameter configuration based on the received control instructions to adjust the frequency of each amplifier so that the pre-amplifier has the same or associated operating frequency as the voltage-controlled oscillator. The pre-amplifier amplifies the signals in the current channel of the communication system and suppresses the signals outside the current channel; that is, similar narrowband amplification characteristics are realized in a broadband communication system, and very good out-of-band suppression performance is achieved.

[0019] Furthermore, the control instructions formed based on the calibration of the voltage-controlled oscillator realize the association between the frequency in the pre-amplifier and the current channel of the system, so that the frequency of the pre-amplifier follows the response of the voltage-controlled oscillator to the current channel of the system, realizing the automatic follow-up of the frequency in the pre-amplifier.

[0020] To make the above and other objects, features and advantages of the present invention more obvious and understandable, the following specifically enumerates preferred embodiments and, in conjunction with the accompanying drawings, makes a detailed description as follows. Brief Description of the Drawings

[0021] Figure 1 Shown are the existing broadband radio frequency communication system and the frequency response curves corresponding to each node.

[0022] Figure 2 Shown is the principle block diagram of the automatic tuning broadband radio frequency communication control device provided by the present invention.

[0023] Figure 3 Shown is the structural schematic diagram of the automatic tuning broadband radio frequency communication system provided in Embodiment 1 of the present invention.

[0024] Figure 4 Shown is Figure 3 The schematic diagram of the frequency response after tuning of two cascaded amplifiers in the automatic tuning broadband radio frequency communication control device shown.

[0025] Figure 5 Shown is the flowchart of the automatic tuning broadband radio frequency communication control method provided in Embodiment 1 of the present invention.

[0026] Figure 6 Shown is the structural schematic diagram of two load amplifiers in Embodiment 2.

[0027] Figure 7 Shown is the schematic diagram of the frequency response curve of the pre-amplifier in Embodiment 2.

[0028] Figure 8 Shown is the frequency response curve after the simple cascading of two traditional amplifiers. Detailed implementation manners

[0029] Embodiment 1

[0030] In Figure 1 , both the first-stage amplifier and the second-stage amplifier are traditional wideband amplifiers, which are used to amplify the signals received by the antenna. From its frequency response, it can be seen that the traditional wideband amplifier amplifies the signals within the total bandwidth (BW) without difference. In Figure 1 , the total bandwidth of the signal is the BW range described by the arrow, but when the communication system is working, only one channel of the bandwidth is occupied, and n channels are represented by Ch1 to Chn. When the current communication selects Ch1, ideally, the signals within the bandwidths of Ch2 to Chn do not actually need to be amplified. If amplified without difference, more noise will enter the system, deteriorating the signal-to-noise ratio of the system.

[0031] In view of this, this embodiment provides an automatic tuning wideband radio frequency communication control device that can obtain the advantages of narrowband communication in a wideband communication system, realizing that the signals within the current channel of the communication system are amplified while the out-of-band signals can be well suppressed. In this embodiment, as Figure 2 shown, the automatic tuning wideband radio frequency communication control device provided in this embodiment includes a pre-stage amplifier 10, a frequency control unit 20, and a feedback unit 30. The pre-stage amplifier 10 includes at least one frequency-tunable amplifier and at least one amplifier load connected to each amplifier. The frequency band of the pre-stage amplifier 10 covers multiple channels required for the operation of the communication system, that is, the pre-stage amplifier 10 is a wideband amplifier. The frequency control unit 20 includes a voltage-controlled oscillator (abbreviation: VCO) 21 and a self-calibration module 22. The self-calibration module 22 calibrates the local oscillator output from the voltage-controlled oscillator 21 to the mixer 50 based on the current channel of the communication system, and forms a control instruction associated with the calibrated local oscillator. The feedback unit 30 synchronously outputs the control instruction generated by the self-calibration module 22 to each amplifier load in the pre-stage amplifier 10. Each amplifier load adjusts its load parameters based on the control instruction, and adjusts the frequency of each amplifier so that the pre-stage amplifier 10 has the same or associated operating frequency as the voltage-controlled oscillator 21. The pre-stage amplifier 10 amplifies the signals within the current channel of the communication system and suppresses the signals outside the current channel. The "associated" refers to the relationship in which the frequency of the pre-stage amplifier follows the local oscillator of the voltage-controlled oscillator and changes according to a preset rule, such as changing in a set ratio.

[0032] In this embodiment, while the self-calibration module 22 calibrates the local oscillator of the voltage-controlled oscillator 21 based on the current channel of the communication system, it generates a control instruction associated with the calibrated local oscillator. When the amplifier load receives this control instruction, it will adjust the parameters of its internal components to achieve frequency adjustment of the amplifier connected thereto, so that the frequency of the preamplifier 10 can follow the local oscillator of the voltage-controlled oscillator 21 for response, thereby enabling the signal within the current channel of the communication system to be amplified while the out-of-band signal is suppressed. That is, the frequency of the preamplifier with broadband characteristics is automatically tuned through the control instruction locked by the local oscillator frequency of the voltage-controlled oscillator, making it have narrowband characteristics.

[0033] In this embodiment, as Figure 3 shown, the preamplifier 10 includes two cascaded band-pass amplifiers A1 and A2 and two LC loads LC1 and LC2 respectively connected to the two band-pass amplifiers A1 and A2. Since the two LC loads LC1 and LC2 have the same topology as the voltage-controlled oscillator, in this embodiment, the control instruction is the value of the calibration control word of the capacitor array C0 in the voltage-controlled oscillator 21 (represented by C bank). The LC loads LC1 and LC2 in the preamplifier adjust the configuration of their capacitor array C1 based on the value of the calibration control word of the capacitor array C0, changing the center frequency of the amplifiers A1 and A2 connected to the LC loads. The value of the calibration control word is the value of the control word corresponding to the capacitor array C0 when the voltage-controlled oscillator 21 outputs with the calibrated local oscillator. However, the present invention does not make any limitation on the specific type of the control instruction. In other embodiments, when the amplifier load is a resistive feedback load, the control instruction is an electrical signal associated with the local oscillator for adjusting the change of the variable resistance value, such as the current-resistance signal in Embodiment 2.

[0034] As Figure 3 shown, each LC load includes a variable inductor L1 and a variable capacitor array C1 connected in parallel; after being connected in parallel, the two are connected to each amplifier through two transistors and a package ground wire ( Figure 3 not shown in the figure). In this embodiment, the two LC loads LC1 and LC2 are formed by transistors and capacitor arrays having the same size as the voltage-controlled oscillator 21. Therefore, simply assigning the value of the calibration control word in the voltage-controlled oscillator 21 (represented in binary form) to the capacitor array C1 in the two LC loads LC1 and LC2 can achieve the frequency following characteristic, and the adjustment of the configuration is very simple. However, the present invention does not make any limitation on this. In other embodiments, the transistor sizes and capacitor arrays on the two LC loads LC1 and LC2 can also be different from those of the voltage-controlled oscillator, and can also be adjusted based on the change trend of the control word value of the capacitor array in the voltage-controlled oscillator during frequency following.

[0035] Figure 3The figure shows a schematic structural diagram of an automatic tuning broadband radio frequency communication system provided in Embodiment 1 of the present invention. Figure 4 Shown as Figure 3 The frequency response schematic diagram of two cascaded amplifiers in Figure 5 The figure shows a flowchart of an automatic tuning broadband radio frequency communication control method provided in Embodiment 1 of the present invention. Combining Figures 3 to 5 The working principle of the automatic tuning broadband radio frequency communication control device provided in this embodiment will be described in detail.

[0036] Specifically, when the broadband communication system operates on a certain channel Chn (Chn represents the nth channel) within the bandwidth, step S10 is executed. The self-calibration module 21 in the frequency control unit 20 will calibrate the local oscillator (LO) output from the voltage-controlled oscillator (VCO) 21 to the mixer based on the current channel Chn of the communication system, and form a control instruction associated with the calibrated local oscillator, that is, this calibration will give the value of the calibration control word of the capacitor array C0 in the voltage-controlled oscillator 21. After obtaining the value of the calibration control word, step S20 is executed, and the value of the calibration control word is synchronously input into each LC load in the pre-stage amplifier. Finally, step S30 is executed, and the value of the voltage-controlled oscillator calibration control word is written into the capacitor array C1 of each LC load, so that both amplifiers A1 and A2 in the pre-stage amplifier 10 have the same frequency characteristics as the voltage-controlled oscillator 21. At this time, combining Figure 4 From the frequency response curves of Figure 4 it can be seen that in figures (c) and (d), the effective signals within the bandwidth of channel Chn after combination will be amplified, and the signals outside the bandwidth of channel Chn will be suppressed by the narrowband characteristics of the pre-stage amplifier and not fully amplified. That is, within the total bandwidth BW, the amplification of the effective signals within the target channel and the suppression of the out-of-band signals are simultaneously achieved, thereby improving the anti-interference characteristics and noise level of the system, and enabling the broadband communication system to obtain the advantages of a narrowband communication system. In Figure 4 figure (a) is the frequency response curve of amplifier A1 after tuning; (b) is the frequency response curve of amplifier A2; (c) is the frequency response curve of the combination of the two amplifiers; (d) is a partial enlarged schematic diagram of figure (c) near Chn. From Figure 4 it can be seen that compared with figures (a) and (b) of the curve graph, the roll-off coefficient of the curve formed by superimposing the two in figure (c) will be larger, and the rate of decline of the curve on both sides of channel Chn is faster. Therefore, the curve formed by superimposition can better suppress the signals outside Chn, thereby achieving narrowband characteristics. Figure 4 In figures (a), (b), and (c), the three curves respectively represent the frequency response curves after tuning under three different input signals; among them, curves A1' and B1' are superimposed to form C1'; curves A2' and B2' are superimposed to form C2'; curves A3' and B3' are superimposed to form C3'.

[0037] When the operating frequency band of the communication system changes to another channel, such as changing from Ch1 to Ch3, steps S10 to S30 are executed again. The self-calibration module 22 calibrates the capacitor array C0 in the voltage-controlled oscillator 21 to generate another local oscillator signal corresponding to the channel Ch3 and simultaneously generates the value of another corresponding calibration control word. The value of this other calibration control word is given to the capacitor array C1 of the two LC load amplifiers in the pre-amplifier, thereby achieving frequency tracking.

[0038] To better match the broadband communication system, preferably, the amplifier A1 is set as a band-pass amplifier with broadband matching characteristics, that is, the bandwidth of the amplifier A1 is greater than the bandwidth of the amplifier A2. However, the present invention does not make any limitations in this regard. In other embodiments, the pre-amplifier may also only use one amplifier with a matching system bandwidth BW and an adjustable center frequency.

[0039] In this embodiment, the frequency control unit 20 is a phase-locked loop circuit integrating frequency adjustment and phase adjustment. However, the present invention does not make any limitations in this regard. In other embodiments, the frequency control unit 20 may also be an automatic frequency controller with only a frequency adjustment function.

[0040] To compensate for the gain difference in a wide frequency range, in this embodiment, the automatic tuning broadband radio frequency communication control device further includes a power detection circuit 40 connected to the output end of the mixer 50 in the communication system. The power detection circuit 40 detects the output power or amplitude of the mixer 50, and the detection result is compared with a preset value. If the amplitude or power output by the mixer is too small, the system increases the gain of the pre-amplifier 10; conversely, when the amplitude or power is too large, the system decreases the gain of the pre-amplifier 10; when the amplitude or power output meets the preset power output requirement, the gain calibration is completed. The present invention does not make any limitations on the specific circuit structure of the power detection circuit 40; it can use a traditional RSSI power detection circuit or other circuits that can implement power or amplitude detection.

[0041] Correspondingly, as Figure 3 shown, this embodiment also provides an automatic tuning broadband radio frequency communication system, which includes the above automatic tuning broadband radio frequency communication control device, mixer 50, filter, VGA, and ADC. Specifically, the radio frequency signal is amplified by the pre-amplifiers A1 and A2 and then input to the mixer 50, where it is mixed with the local oscillator output by the frequency control unit 20 and then output. The feedback unit 30 is connected between the frequency control unit 20 and the pre-amplifier 10, and the value of the calibration control word (C bank) generated by the calibration of the frequency control unit 20 is output to the pre-amplifier 10. The power detection circuit 40 detects the power or amplitude of the output of the mixer 50 and feeds it back to the pre-amplifier 10.

[0042] Embodiment Two

[0043] Since the chip area and optimization cost required by a broadband amplifier are both very high, to solve this problem, in this embodiment, based on Embodiment 1, two cascaded narrowband amplifiers are adopted to form the preamplifier 10. The frequency and roll-off coefficient of each amplifier are adjusted based on the control instruction output by the frequency control unit 20, so that the preamplifier 10 formed after the two narrowband amplifiers are cascaded can achieve broadband-like characteristics while satisfying the frequency response follow-up to match the broadband communication system, thereby well solving the problem of high cost brought by using a broadband amplifier.

[0044] Combined with Figure 3 and Figure 6 , in this embodiment, the preamplifier 10 includes two cascaded amplifiers. Among them, the amplifier A1 at the first stage is a low-pass amplifier and the amplifier load connected to it is a resistive feedback load RI; the amplifier A2 at the second stage is a band-pass amplifier and the amplifier load connected to it is an LC load LC3. However, the present invention does not make any limitation in this regard. In other embodiments, the first-stage amplifier A1 can also be a band-pass amplifier, and the second-stage amplifier can be a high-pass amplifier.

[0045] In this embodiment, the maximum gain values of the two amplifiers are equal, both being Gm. Based on the control instruction output by the frequency control unit 20, each amplifier load adjusts the frequency and roll-off coefficient of the amplifier connected to it, so that a communication system current channel is formed between the corner frequency (corner freq1) of amplifier A1 and the center frequency (freq2) of amplifier A2, and each frequency point within this frequency range has an equal or close gain. The "close" means that the difference between the actual gain of the frequency point in this area and the superimposed preset gain does not exceed 1 dB. However, the present invention does not make any limitation in this regard. In actual optimization design, the parameters of variable components can be continuously adjusted to make the gains of all frequency points within corner freq1 to freq2 infinitely close, so as to form a relatively flat band-pass characteristic within corner freq1 to freq2.

[0046] Figure 8The figure shows the frequency response curve after the simple cascading of two traditional amplifiers. Among them, curve L01 is the frequency response curve of the low-pass amplifier, and curve L02 is the frequency response curve of the band-pass amplifier with an LC load; curve L03 is the frequency response curve after the superposition of the two. It can be seen from the figure that the maximum gain Gm of the frequency response curves of the two amplifiers is 10 dB, and the gain at the overlapping part is 8 dB; therefore, after the two-stage amplifiers are cascaded together, in curve L03, the gains at the leftmost and rightmost sides are 10 + 1 = 11 dB, and the gain at the overlapping part in the middle is 16 dB. It can be obtained that the simple cascading of two narrow-band amplifiers cannot form a wide-band characteristic, that is, it is impossible to achieve the wide-band characteristic that the gains at each frequency point within the required channel are equal or close.

[0047] In this embodiment, the adjustment of the roll-off coefficient of each amplifier is introduced while the frequency is tuned. The roll-off coefficient is closely related to the rising and falling rates of the edges in the amplifier frequency response curve. Figure 7 The figure shows the superposed frequency response curve after the frequency and roll-off coefficient adjustment of two amplifiers in the pre-stage amplifier in this embodiment. Among them, curve L11 is the frequency response curve of the low-pass amplifier, and curve L12 is the frequency response curve of the band-pass amplifier with an LC load; curve L13 is the frequency response curve after the superposition of the two. After adjustment, the falling rate on the right side of curve L11 is made consistent with the rising rate on the left side of curve 12. At the same time, the sum of the gains at the overlapping part of the two is 11 dB, and the sum of the gains at the corner frequency (corner freq1) of the low-pass amplifier is also 11 dB. At the center frequency freq2 of the band-pass amplifier, the sum of the gains of the two is also 11 dB. In this way, within the entire frequency band from corner freq1 to freq2, a relatively flat band-pass characteristic can be obtained. And the frequency band from corner freq1 to freq2 obtained after the frequency following response adjustment is the current channel of the communication system, so as to realize that the effective signals within the current channel of the communication system are uniformly amplified, while the signals outside the band are not fully amplified and are suppressed.

[0048] Its working principle is as follows: The communication bandwidth of the system is divided into multiple channels so that the maximum achievable bandwidth of the preamplifier (which can be understood as the bandwidth between corner freq1 and freq2) can be covered. For example, when the communication signal bandwidth is 1G and the achievable bandwidth of the preamplifier is 250M, the communication signal bandwidth can be divided into four channels, namely Ch1, Ch2, Ch3, and Ch4. When the broadband communication system operates on a certain channel Ch1 within the bandwidth, the self-calibration module 21 in the frequency control unit 20 will calibrate the local oscillator (LO) output from the voltage-controlled oscillator (VCO) 21 to the mixer based on the current channel Ch1 of the communication system, and form a control instruction associated with the calibrated local oscillator. Then, the feedback unit 30 will output the control instruction to the two amplifier loads in the preamplifier 10. Based on the control instruction, each amplifier load adjusts the parameters of its variable device, thereby adjusting the frequencies corner freq1, freq2 and the roll-off coefficient of the two amplifiers A1 and A2 to meet Figure 7 the requirements shown, where channel Ch1 is the frequency band between corner freq1 and freq2. When the channel of the communication system is adjusted to Ch2, based on another control instruction formed after the calibration of the voltage-controlled oscillator, the two amplifier loads respectively adjust the corresponding component parameters in the regulator to achieve the adjustment of corner freq1 and freq2 so that the frequency band between corner freq1 and freq2 matches channel Ch2 and the roll-off coefficients of both also meet the requirement that the gain at any point is close to the maximum gain of the two amplifiers.

[0049] In this embodiment, by dividing the broadband signal of the system into multiple channels and adopting a combined configuration of a preamplifier for each channel to achieve frequency tracking and the required broadband characteristics within the channel, it has very good in-band amplification characteristics and out-of-band suppression performance. The combination of multiple preamplifier configurations also enables the entire communication system to have good broadband characteristics, that is, the broadband characteristics are achieved through the cascading of narrowband amplifiers. For each combination of amplifier configurations, after configuration, it can be directly written through the register based on the change of the communication system channel, and the adjustment is very convenient.

[0050] In the automatic tuning broadband radio frequency communication control device provided in this embodiment, based on the adjustment of the frequency and the roll-off coefficient, the preamplifier 10 can adopt two narrowband amplifiers to achieve broadband characteristics to match the requirements of the broadband system. Compared with using broadband amplifiers, narrowband amplifiers have a smaller volume, require less current for operation, and the cost of optimized design will also be better, thus being able to better meet the requirements of low-cost fields.

[0051] The following will be combined with Figure 6To introduce in detail the adjustment of the frequency and roll-off coefficient of the preamplifier. In this embodiment, one of the loads in the preamplifier is a resistor feedback load RI, and the other is an LC load LC3. The transistor size and capacitance array C3 in the LC load are the same as those in the voltage-controlled oscillator 21. The control instruction formed after the calibration of the voltage-controlled oscillator includes the value of the calibration control word output to the LC load.

[0052] As Figure 6 shown, the resistor feedback load includes a variable feedback resistor R1, switching transistors M1, M2, and a variable current source I1. The variable current source I1, switching transistors M1, and M2 are connected in series in turn between the power supply and the first package ground wire CND1. The radio frequency input IN is connected to the series connection point of the switching transistors M1 and M2 through the variable feedback resistor R1, and the control electrodes of the two switching transistors M1 and M2 are connected. Specifically, the smaller the current output by the variable current source I1 and the larger the variable feedback resistor R1, the more corner freq1 moves in the low-frequency direction ( Figure 7 the left side of the coordinate system in the figure) and the falling rate on the right side of the curve will increase. On the contrary, when the current output by the variable current source I1 is larger and the variable feedback resistor R1 is smaller, corner freq1 moves in the high-frequency direction and the falling rate on the right side of the curve will decrease. Based on this adjustment rule and the resistor-current adjustment signal as the control instruction, the variable feedback resistor R1 and the variable current source I1 are adjusted to achieve the adjustment of the bandwidth and roll-off coefficient of the low-pass amplifier. In addition, broadband matching of impedance can be achieved by further optimizing the sizes of the variable feedback resistor R1, the variable current source I1, and the first package ground wire GND1. This method can be achieved without off-chip components; and if the radio frequency input port is connected by a bonding wire, very good broadband characteristics can be achieved through design adjustment.

[0053] For the LC load LC3, it includes a capacitance array C2, an adjustable inductor L2, a variable resistor R2, and switching transistors M3, M4. The adjustable inductor L2 and the variable resistor R2 are connected in series and then in parallel with the capacitance array C3 to form an adjustment module. The adjustment module is connected to the band-pass amplifier through the series-connected switching transistors M4, M3, and the second package ground wire GND2. The connection point between the adjustment module and the switching transistor M4 forms the radio frequency output OUT. Based on the control instruction, the capacitance array C2 and the adjustable inductor L2 are adjusted to change the center frequency of the amplifier A2, and the variable resistor R2 is adjusted to change the roll-off coefficient on the low-frequency side of the amplifier A2. This stage of the amplifier A2 has a band-pass characteristic. The capacitance array C2 and the adjustable inductor L2 are used to achieve a large range of frequency adjustment, the adjustable resistor R2 is used to adjust the roll-off coefficient of the band-pass at different frequency points, and the variable current bias circuit 60 is used for the absolute gain of the second-stage amplifier, so as to achieve the optimal superposition of the gain curves of the two-stage amplifiers and meet the requirements of broadband characteristics.

[0054] In summary, in the automatic tuning broadband radio frequency communication control device, method and system provided by the present invention, the amplifiers located in the preamplifier are all of a frequency-adjustable structure, and the frequency band of the preamplifier covers multiple channels required for the operation of the communication system, that is, the preamplifier has broadband characteristics. The frequency control unit forms corresponding control instructions when calibrating the local oscillator output by the voltage-controlled oscillator based on the current channel of the communication system, and synchronously outputs the control instructions to each amplifier load in the preamplifier. Each amplifier load adjusts its parameter configuration based on the received control instruction to adjust the frequency of each amplifier so that the preamplifier has the same or associated operating frequency as the voltage-controlled oscillator. The preamplifier amplifies the signals in the current channel of the communication system and suppresses the signals outside the current channel; that is, a narrowband-like amplification characteristic is realized in a broadband-characteristic communication system, and it has very good out-of-band suppression performance.

[0055] Furthermore, the control instructions formed based on the calibration of the voltage-controlled oscillator realize the association between the frequency in the preamplifier and the current channel of the system, so that the frequency of the preamplifier follows the response of the voltage-controlled oscillator to the current channel of the system, realizing the automatic following of the frequency in the preamplifier.

[0056] Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in this art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope claimed in the claims.

Claims

1. An automatic tuning broadband radio frequency communication control device, characterized in that, Comprising: A preamplifier, including two cascaded amplifiers and at least one amplifier load connected to each amplifier, the frequency band of the preamplifier covering multiple channels required for the operation of the communication system; A frequency control unit, including a voltage-controlled oscillator and a self-calibration module, the self-calibration module calibrating the local oscillator output from the voltage-controlled oscillator to the mixer based on the current channel of the communication system and forming a control instruction associated with the calibrated local oscillator; A feedback unit, synchronously outputting the control instruction generated by the self-calibration module to each amplifier load within the preamplifier, each amplifier load adjusting its load parameter based on the control instruction, adjusting the frequency of each amplifier so that the preamplifier has the same or associated operating frequency as the voltage-controlled oscillator, and the preamplifier amplifying the signal within the current channel of the communication system and suppressing the signals outside the current channel; Among the two cascaded amplifiers, one is a low-pass amplifier and the amplifier load connected thereto is a resistive feedback load; the other is a band-pass amplifier and the amplifier load connected thereto is an LC load; the maximum gain values of the two amplifiers are equal, and based on the control instruction output by the frequency control unit, each amplifier load adjusts the frequency and roll-off coefficient of the amplifier connected thereto, a current channel of the communication system is formed between the inflection point frequency of the low-pass amplifier and the center frequency of the band-pass amplifier, and each frequency point within this frequency range has an equal or approximate gain, where "approximate" means that the difference between the actual gain of the frequency points within this range and the superimposed preset gain does not exceed 1 dB.

2. The automatic tuning broadband radio frequency communication control device according to claim 1, wherein When the amplifier load is an LC load, the control instruction is the value of the calibration control word of the capacitor array within the voltage-controlled oscillator, and the LC load within the preamplifier adjusts the configuration of its capacitor array based on the value of the calibration control word of the capacitor array, changing the frequency of the amplifier connected to the LC load; the value of the calibration control word is the value of the control word of the capacitor array when the voltage-controlled oscillator outputs with the calibrated local oscillator.

3. The automatic tuning broadband radio frequency communication control device according to claim 1, characterized in that The automatic tuning broadband radio frequency communication control device further includes a power detection circuit, the power detection circuit being connected to the output of the mixer within the communication system, detecting the output power or amplitude of the mixer and feeding it back to the preamplifier.

4. An automatic tuning broadband radio frequency communication control method, characterized in that, Comprising: Calibrating the local oscillator output from the voltage-controlled oscillator to the mixer based on the current channel of the communication system and forming a control instruction associated with the calibrated local oscillator; Synchronously outputting the control instruction generated by the self-calibration module to each amplifier load within the preamplifier, the preamplifier including two cascaded amplifiers with equal maximum gain values and at least one amplifier load connected to each amplifier, the frequency band of the preamplifier covering multiple channels required for the operation of the communication system; Each amplifier load adjusts its load parameter based on the control instruction, adjusting the frequency of each amplifier so that the preamplifier has the same or associated operating frequency as the voltage-controlled oscillator, and the preamplifier amplifying the signal within the current channel of the communication system and suppressing the signals outside the current channel; Among the two cascaded amplifiers, one is a low-pass amplifier and the other is a band-pass amplifier; The automatic tuning broadband radio frequency communication control method further includes: based on the control instruction output by the frequency control unit, each amplifier load adjusts the roll-off coefficient of the amplifier connected thereto, and a communication system current channel is formed between the inflection point frequency of the low-pass amplifier and the center frequency of the band-pass amplifier, and each frequency point within this frequency range has an equal or approximate gain, where "approximate" means that the difference between the actual gain of the frequency point within this range and the superimposed preset gain does not exceed 1 dB.

5. The automatic tuning broadband radio frequency communication control method according to claim 4, wherein When the amplifier load is an LC load, the control instruction is the value of the calibration control word of the capacitor array in the voltage-controlled oscillator, and the LC load in the pre-stage amplifier adjusts the configuration of its capacitor array based on the value of the calibration control word of the capacitor array, changing the frequency of the amplifier connected to the LC load; the value of the calibration control word is the value of the control word of the capacitor array when the voltage-controlled oscillator outputs the calibrated local oscillator.

6. An automatic tuning broadband radio frequency communication system, characterized in that, Including: The automatic tuning broadband radio frequency communication control device according to any one of claims 1 to 3; A mixer, the output of the pre-stage amplifier and the frequency control unit are respectively connected to the input of the mixer.

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