A frequency synthesizing module

Abstract

The application discloses a frequency synthesizer module, and relates to the technical field of radio frequency frequency synthesis, which comprises a control board, a fixed local oscillator board, a frequency hopping local oscillator board and a power division clock board. The control board comprises a programmable logic device, a serial interface circuit and a voltage conversion circuit. The programmable logic device is connected with the first phase-locked synthesizer and the second phase-locked synthesizer through the serial interface circuit. The voltage conversion circuit is connected with the fixed local oscillator board, the frequency hopping local oscillator board and the power division clock board. The power division clock board comprises a phase-locked crystal oscillator circuit and a clock power division network. The output end of the phase-locked crystal oscillator circuit is connected with the input end of the clock power division network. The first output end of the clock power division network is connected with the reference input end of the first phase-locked synthesizer. The second output end of the clock power division network is connected with the reference input end of the second phase-locked synthesizer. At least one output end of the clock power division network is used as the clock output end of the frequency synthesizer module. The frequency synthesizer module can accurately control the output power, suppress the stray and improve the spectral purity, thereby ensuring excellent phase noise performance and controllable frequency hopping time.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radio frequency synthesis technology, and in particular to a frequency synthesis module. BACKGROUND

[0002] With the continuous development of radio frequency systems, frequency synthesis modules, as key generation and processing units for radio frequency signals, are widely used in communication, radar, and test equipment. Current frequency synthesis modules mainly rely on stable generation and high-precision tuning of local oscillator signals to ensure that the system can provide accurate signal output within multiple frequency bands. In recent years, with the advancement of technology, the performance of frequency synthesis modules has been continuously improved, especially in terms of frequency range, phase noise, and spurious suppression. Modern frequency synthesis modules use high-stability clock sources and precise phase-locked synthesis techniques to meet high requirements for frequency accuracy and phase noise standards.

[0003] However, existing frequency synthesis modules still face some challenges in multi-band output, frequency hopping performance, and monitoring control. For example, the frequency synthesis modules in the prior art may have problems such as insufficient flexibility in frequency adjustment steps, long frequency hopping time, and insufficient state monitoring capability in complex environments. These problems may cause the system to be unstable during frequency switching or unable to respond in a timely manner to the impact of environmental changes. SUMMARY

[0004] In view of the above existing problems, the present application is proposed.

[0005] Therefore, the present application provides a frequency synthesis module to solve the problems of inflexible frequency step adjustment, long frequency hopping switching time, and insufficient running state monitoring capability.

[0006] To solve the above technical problems, the present application provides the following technical solutions:

[0007] In a first aspect, the present application provides a frequency synthesis module, which includes a control board, a fixed local oscillator board, a frequency hopping local oscillator board, a power division clock board, a fixed local oscillator power division amplification unit, and a frequency hopping local oscillator power division amplification unit.

[0008] The control board includes a programmable logic device, a serial interface circuit, and a voltage conversion circuit. The programmable logic device is connected to a first phase-locked synthesizer and a second phase-locked synthesizer through the serial interface circuit, and the voltage conversion circuit is connected to the fixed local oscillator board, the frequency hopping local oscillator board, and the power division clock board.

[0009] The output end of the fixed local oscillator power division amplification unit serves as a fixed local oscillator output end, and the output end of the frequency hopping local oscillator power division amplification unit serves as a frequency hopping local oscillator output end.

[0010] The fixed local oscillator board comprises a first phase-locked synthesizer, a first voltage-controlled oscillator, a first frequency multiplier and a first band-pass filter, and the output end of the first band-pass filter is connected with the input end of the fixed local oscillator power division amplification unit through a first local oscillator switch circuit.

[0011] The frequency hopping local oscillator board comprises a second phase-locked synthesizer, a second voltage-controlled oscillator, a second frequency multiplier and a segmented band-pass filter group connected in series, and the output end of the segmented band-pass filter group is connected with the input end of the frequency hopping local oscillator power division amplification unit through a second local oscillator switch circuit.

[0012] The power division clock board comprises a phase-locked crystal oscillator circuit and a clock power division network, the output end of the phase-locked crystal oscillator circuit is connected with the input end of the clock power division network, the first output end of the clock power division network is connected with the reference input end of the first phase-locked synthesizer, the second output end of the clock power division network is connected with the reference input end of the second phase-locked synthesizer, and at least one output end of the clock power division network is used as the clock output end of the frequency synthesizer module.

[0013] As a preferred scheme of the frequency synthesizer module, in the fixed local oscillator board, the first voltage-controlled oscillator outputs at least two point frequency signals, one point frequency signal is output through a first channel of the first band-pass filter, and the other point frequency signal is output through a second channel of the first band-pass filter and the first frequency multiplier.

[0014] The first local oscillator switch circuit selects between the first channel output and the second channel output and connects the selected channel output to the input end of the fixed local oscillator power division amplification unit.

[0015] As a preferred scheme of the frequency synthesizer module, the output frequency of the second voltage-controlled oscillator is adjusted at a fixed frequency interval in a first frequency range, the output frequency of the second frequency multiplier is adjusted at a corresponding frequency interval in a second frequency range, and the segmented band-pass filter group comprises a plurality of band-pass filter channels, and the plurality of band-pass filter channels correspond to a plurality of sub-frequency bands in the second frequency range respectively.

[0016] As a preferred scheme of the frequency synthesizer module, the programmable logic device communicates with the first phase-locked synthesizer and the second phase-locked synthesizer through a serial peripheral interface protocol, and the serial peripheral interface protocol comprises a clock signal line, a chip selection signal line and a data line.

[0017] As a preferred scheme of the frequency synthesizer module, the first local oscillator switch circuit selects between a first fixed local oscillator frequency channel and a second fixed local oscillator frequency channel, the fixed local oscillator power division amplification unit receives a fixed local oscillator output signal from the selected channel and provides a plurality of fixed local oscillator output ends.

[0018] As a preferred scheme of the frequency synthesizer module, the second voltage-controlled oscillator generates a plurality of groups of frequency hopping radio frequency signals according to a frequency sequence given by the frequency configuration word, the second frequency multiplier outputs a plurality of groups of frequency hopping local oscillator candidate signals, the segmented band-pass filter group selects a target band-pass filter channel in a plurality of band-pass filter channels, and the frequency hopping local oscillator power division amplification unit receives a frequency hopping local oscillator output signal from the target band-pass filter channel and provides a plurality of frequency hopping local oscillator output terminals.

[0019] As a preferred scheme of the frequency synthesizer module, the control board accesses internal state registers of the first phase-locked synthesizer and the second phase-locked synthesizer to read locking state information, accesses a temperature acquisition circuit register to read internal temperature information of the frequency synthesizer module, and generates a state monitoring result.

[0020] As a preferred scheme of the frequency synthesizer module, the state monitoring result is compared with a threshold parameter to determine the working state of the fixed local oscillator board and the frequency hopping local oscillator board.

[0021] As a preferred scheme of the frequency synthesizer module, when the state monitoring result indicates an alarm state, the control board reissues a frequency configuration word and a working mode configuration word, the control board outputs alarm information through an external communication interface, and the fixed local oscillator output terminal and the frequency hopping local oscillator output terminal are closed.

[0022] The frequency synthesizer module can provide a plurality of point frequency and wideband frequency hopping local oscillator outputs in a single component through the cooperative work of the unified reference clock, the double-phase-locked local oscillator link, and the power division amplification unit. The frequency synthesizer module can ensure excellent phase noise performance and controllable frequency hopping time through accurate control of output power, spurious suppression, and spectral purity. On the basis of the integration of the fixed point frequency source and the wideband frequency hopping source, the demand for external local oscillator sources is reduced, and the flexibility of frequency configuration and the compactness of the system are improved. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0024] Fig. 1 The figure is an architecture diagram of the frequency synthesizer module.

[0025] Fig. 2 The figure is a functional block diagram of the fixed local oscillator power division amplification unit.

[0026] Fig. 3 The figure is a functional block diagram of the frequency hopping local oscillator power division amplification unit.

[0027] Fig. 4 Flow chart for frequency and power control. DETAILED DESCRIPTION

[0028] In order to make the above objectives, features and advantages of the present application more clear and comprehensible, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0029] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details given herein, that the present application can be practiced with other than the described embodiments and that variations from the particular embodiments described herein can be made and still be within the scope of the present application.

[0030] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. The "in one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments.

[0031] Embodiment 1, with reference to Figs. 1-4 For one embodiment of the present application, the embodiment provides a frequency synthesizer module, comprising the following modules: a control board, a fixed local oscillator board, a frequency hopping local oscillator board, a power division clock board, a fixed local oscillator power division amplification unit and a frequency hopping local oscillator power division amplification unit;

[0032] The control board comprises a programmable logic device, a serial interface circuit and a voltage conversion circuit, the programmable logic device is connected with the first phase-locked synthesizer and the second phase-locked synthesizer through the serial interface circuit respectively, and the voltage conversion circuit is connected with the fixed local oscillator board, the frequency hopping local oscillator board and the power division clock board respectively;

[0033] The output end of the fixed local oscillator power division amplification unit is used as a fixed local oscillator output end, and the output end of the frequency hopping local oscillator power division amplification unit is used as a frequency hopping local oscillator output end;

[0034] The fixed local oscillator board comprises a first phase-locked synthesizer, a first voltage-controlled oscillator, a first frequency multiplier and a first band-pass filter, and the output end of the first band-pass filter is connected with the input end of the fixed local oscillator power division amplification unit through a first local oscillator switch circuit;

[0035] The frequency hopping local oscillator board comprises a second phase-locked synthesizer, a second voltage-controlled oscillator, a second frequency multiplier and a segmented band-pass filter group connected in series, and the output end of the segmented band-pass filter group is connected with the input end of the frequency hopping local oscillator power division amplification unit through a second local oscillator switch circuit;

[0036] The power division clock board comprises a phase-locked crystal oscillator circuit and a clock power division network, the output end of the phase-locked crystal oscillator circuit is connected with the input end of the clock power division network, the first output end of the clock power division network is connected with the reference input end of the first phase-locked synthesizer, the second output end of the clock power division network is connected with the reference input end of the second phase-locked synthesizer, and at least one output end of the clock power division network is used as the clock output end of the frequency synthesizer module.

[0037] Specifically, the input end receives a 100MHz reference clock signal, and after being processed by the phase-locked crystal oscillator circuit and the clock power division network in the power division clock board, the reference signal is provided to the first phase-locked synthesizer and the second phase-locked synthesizer as a phase-locked reference under the premise that the reference precision is about ±0.05ppm and the reference phase noise is not higher than -155dBc / Hz at 1kHz frequency offset, and meanwhile, two 100MHz clock signals are output from the front panel, the output power is in the range of 5dBm-7dBm, the spurious component is not higher than -72dBc, and the clock signals are used to provide a unified clock reference for external devices.

[0038] The programmable logic device in the control board communicates with the first phase-locked synthesizer and the second phase-locked synthesizer through a serial interface, and writes frequency configuration data (including multiple frequency configuration words) in address 0x0A according to the frame format of 1bit read / write bit, 7bit address bit and 16bit data bit, so that the radio frequency is tuned in the range of 22GHz-42GHz with a step of 10MHz, and at the same time, the frequency hopping local oscillator locking indication, the fixed local oscillator locking indication and the temperature information are read through the state registers in addresses 0x20 and 0x30, so as to realize the frequency control and state monitoring of the local oscillator link.

[0039] Furthermore, the fixed local oscillator board is based on the first phase-locked synthesizer and the first voltage-controlled oscillator working at two point frequencies of 10GHz and 12GHz, the 10GHz signal output by the first voltage-controlled oscillator is sent into the fixed local oscillator power division amplification unit after being filtered and attenuated, the 12GHz signal is converted to 24GHz by the first frequency multiplier, and then is sent into the fixed local oscillator power division amplification unit after being selected by the first band-pass filter and the local oscillator switch, so as to form two point frequency local oscillator channels of 10GHz and 24GHz. The fixed local oscillator power division amplification unit divides the point frequency local oscillator power into two external local oscillator outputs, the output power of each output is not less than +16dBm, the spurious suppression degree is not less than 65dBc, the phase noise at the 10GHz frequency point can be controlled to be not higher than about -84dBc / Hz, -94dBc / Hz, -94dBc / Hz and -98dBc / Hz at frequency offsets of 1kHz, 10kHz, 100kHz and 1MHz respectively, and the phase noise at the 24GHz frequency point can also be controlled to be not higher than about -84dBc / Hz, -94dBc / Hz, -94dBc / Hz and -98dBc / Hz at the frequency offsets, so as to provide low phase noise point frequency local oscillator driving for the external up-down frequency conversion link.

[0040] The frequency hopping local oscillator board works in the frequency range of 11GHz~21GHz based on the second phase-locked synthesizer and the second voltage-controlled oscillator, generates the frequency hopping signal in steps of 5MHz, is converted into the frequency hopping frequency band of 22GHz~42GHz by the second frequency multiplier, enters the segmented band-pass filter group to realize the selection of the sub-band, and is sent into the frequency hopping local oscillator power division amplification unit through the second local oscillator switch circuit. The frequency hopping local oscillator power division amplification unit divides and amplifies the frequency hopping signal in the range of 22GHz~42GHz into two paths of output, the frequency steps are 10MHz, the single frequency hopping time is not more than 300μs, the output power of each path is not less than 16dBm, and the spurious suppression degree is not less than 60dBc; at the typical working frequency point of 28GHz, the phase noise of the frequency hopping local oscillator can reach about -86.2dBc / Hz, -95dBc / Hz, -97dBc / Hz and -97dBc / Hz at 1kHz, 10kHz, 100kHz and 1MHz frequency deviation respectively, which meets the requirements of the local oscillator source phase noise of the high-frequency frequency conversion link.

[0041] The frequency synthesizer module power supply adopts +12V DC power supply, the voltage tolerance range is about +12V±10%, the working current is not more than 1.1A, and the whole machine power consumption is not higher than 10W; the voltage conversion circuit on the control board converts the input +12V voltage into the required multi-path stable voltage power supply of each local oscillator board and power division clock board, and configures the filtering and decoupling network on each board to reduce the influence of power supply ripple and digital switch noise on the phase noise of the phase-locked synthesizer and the voltage-controlled oscillator. The applicable environmental temperature range is -40℃~+60℃, the whole machine weight is not more than 0.35kg, and the reliability and environmental adaptability requirements can be met through structural measures such as shell reinforcement, connector selection and sealing protection. The vibration, impact, humidity, salt spray and transportation conditions can be tested and verified in combination with related military environmental standards to ensure that the frequency synthesizer module maintains the local oscillator frequency stability, output power and phase noise and other indicators within the specified temperature and environmental range to meet the technical index requirements for a long time.

[0042] The first voltage-controlled oscillator in the fixed local oscillator board outputs at least two point frequency signals, one point frequency signal is output through the first channel of the first band-pass filter, and the other point frequency signal is output through the first frequency multiplier and the second channel of the first band-pass filter.

[0043] The first local oscillator switch circuit selects between the first channel output and the second channel output, and connects the selected channel output to the input end of the fixed local oscillator power division amplification unit.

[0044] The specific working process is as follows: the first voltage-controlled oscillator switches the output between two point frequencies of about 10GHz and 12GHz under the locking control of the first phase-locked synthesizer; when the 10GHz point frequency is selected, the 10GHz signal is sent to the first local oscillator switching circuit after being filtered and shaped by the first pass of the first band-pass filter; when the 24GHz point frequency is selected, the 12GHz signal is first subjected to 2 times frequency multiplication by the first frequency multiplier to obtain a signal of about 24GHz, and then is sent to the first local oscillator switching circuit after the fundamental wave and high-order harmonics are filtered out by the second pass of the first band-pass filter. The first local oscillator switching circuit is switched between the 10GHz path and the 24GHz path under the action of the mode control signal output by the control panel, and sends the selected point frequency to the fixed local oscillator power division and amplification unit. The fixed local oscillator power division and amplification unit uses multi-stage amplification in cooperation with a power division network to increase and distribute the local oscillator power into multiple outputs, and the power of a single output is typically not less than 16dBm, the spurious suppression degree is better than about 65dBc, and the phase noise is better than about -90dBc / Hz within a frequency deviation of 1kHz-1MHz, which is used to provide two kinds of point frequencies for an external up-down frequency conversion link, and the local oscillator signals are sufficient in power and relatively pure in spectrum.

[0045] The output frequency of the second voltage-controlled oscillator is adjusted at a fixed frequency interval in the first frequency range, the output frequency of the second frequency multiplier is adjusted at a corresponding frequency interval in the second frequency range, and the segmented band-pass filter group includes a plurality of band-pass filter channels, and the plurality of band-pass filter channels correspond to a plurality of sub-frequency bands in the second frequency range respectively.

[0046] The specific working process is as follows: the second voltage-controlled oscillator outputs a jump signal in the first frequency range of about 11GHz-21GHz under the locking control of the second phase-locked synthesizer, the signal is sent to the second frequency multiplier for 2 times frequency multiplication, the output frequency covers about 22GHz-42GHz, and the frequency step is 10MHz, thereby meeting the frequency hopping local oscillator index of 22GHz-42GHz and 10MHz step.

[0047] The second frequency multiplier output is connected to the segmented band-pass filter group, a plurality of band-pass channels are arranged in the filter group, and the 22GHz-42GHz frequency band is divided into a plurality of sub-frequency bands; the control panel selects the corresponding channel according to the current target frequency point, so that the sub-frequency band where the target frequency point is located passes through, and the remaining frequency bands are effectively suppressed, thereby suppressing the harmonics and out-of-band spurs introduced in the frequency multiplication process. The frequency hopping local oscillator signal output by the segmented band-pass filter group is sent to the frequency hopping local oscillator power division and amplification unit through the second local oscillator switching circuit, the power division and amplification unit increases and distributes the local oscillator power into multiple outputs, the power of a single output is not less than 16dBm, the spurious suppression degree of the full frequency band is better than about 60dBc, the phase noise at a typical 28GHz frequency point is better than about -85dBc / Hz, the frequency hopping time is controlled within the range of about 220μs to 300μs at a frequency deviation of 1kHz, and thereby the frequency hopping local oscillator output is realized in a wide frequency band and is fast and stable.

[0048] The working principle of the frequency synthesizer module is as follows:

[0049] (1) Clock generation and distribution: the external input 100MHz reference clock is stabilized and shaped by the phase-locked crystal oscillator circuit in the clock power division board, and then enters the clock power division network. One way outputs are sent to the first phase-locked synthesizer and the second phase-locked synthesizer as phase-locked reference, and the other way or multiple ways are output as 100MHz clock interface from the front panel. The output power is about 5-7dBm, and the phase noise is better than about -155dBc / Hz@1kHz, which provides a unified low phase noise reference for all local oscillator links.

[0050] (2) Fixed local oscillator link: the first phase-locked synthesizer drives the first voltage-controlled oscillator to work at 10GHz or 12GHz point frequency under the control of the 100MHz reference and the frequency configuration word sent by the control board. The first frequency multiplier and the first band-pass filter form two point frequency local oscillator paths of 10GHz and 24GHz. The first local oscillator switch circuit selects the required path and sends it to the fixed local oscillator power division and amplification unit to form multiple 10GHz / 24GHz point frequency local oscillator outputs.

[0051] (3) Frequency hopping local oscillator link: the second phase-locked synthesizer locks the second voltage-controlled oscillator to output in the range of 11GHz-21GHz with 5MHz step under the same reference clock. The second frequency multiplier expands the frequency hopping range to 22GHz-42GHz. The sub-band band-pass filter group selects and filters the target frequency point, and then the second local oscillator switch circuit and the frequency hopping local oscillator power division and amplification unit generate multiple 22GHz-42GHz, 10MHz step frequency hopping local oscillator outputs.

[0052] (4) Control and monitoring: the programmable logic device in the control board writes frequency configuration words and working mode configuration words to the two-way phase-locked synthesizer through a serial interface, reads the phase-locked state and temperature information, and outputs the state monitoring results and alarm information through an external interface, realizing the unified configuration, frequency hopping sequence issuing and running state monitoring of the frequency synthesizer module to the fixed local oscillator and the frequency hopping local oscillator.

[0053] In summary, the embodiment realizes the simultaneous provision of multiple point frequency and wide frequency band frequency hopping local oscillator outputs in a single component through the cooperative work of the unified reference clock, the double-way phase-locked local oscillator link and the power division and amplification unit. The frequency synthesizer module ensures excellent phase noise performance and controllable frequency hopping time by accurately controlling the output power, spurious suppression and spectral purity. On the basis of integrating fixed point frequency sources and wideband frequency hopping sources, the demand for external local oscillator sources is reduced, and the flexibility of frequency configuration and the compactness of the system are improved.

[0054] Embodiment 2 provides a signal processing method of a frequency synthesizer module, which is based on the frequency synthesizer module in Embodiment 1, and specifically includes the following steps:

[0055] In the clock link, an externally input 100MHz reference clock signal is connected to the power division clock board, the reference clock power is in the range of 0dBm-8dBm, the frequency accuracy is better than ±0.05ppm, the phase noise is better than about -155dBc / Hz at 1kHz frequency offset, the phase-locked crystal oscillator circuit is used to stabilize and shape the reference clock, and then the shaped 100MHz reference signal is sent to the clock power division network, the clock power division network distributes the shaped 100MHz reference signal to the reference input terminals of the first phase-locked synthesizer and the second phase-locked synthesizer respectively, and provides 100MHz clock output with power of 5dBm-7dBm through another output terminal, the output spurious suppression degree is better than about 72dBc, and is used to provide a unified clock reference for external devices.

[0056] In the configuration and control process, the programmable logic device in the control board establishes an SPI communication link with the first phase-locked synthesizer and the second phase-locked synthesizer through the serial interface circuit, the SPI interface includes a clock line, a chip selection line and a data line, the communication adopts a frame format of 1bit read / write bit, 7bit address bit and 16bit data bit; during the power-on initialization and running process of the control board, the frequency configuration word and the working mode configuration word are written into the first phase-locked synthesizer and the second phase-locked synthesizer according to the external control instruction, the frequency configuration word is used to set the fixed local oscillator point frequency (such as 10GHz and 12GHz) and the start frequency, the end frequency and the frequency step (corresponding to 11GHz-21GHz, 5MHz step) of the frequency hopping local oscillator, and the working mode configuration word is used to set the point frequency / frequency hopping working mode, the output enable state and the local oscillator switch channel selection and other parameters.

[0057] In the fixed local oscillator generation process, the first phase-locked synthesizer locks the first voltage-controlled oscillator at the 10GHz or 12GHz point frequency under the action of the 100MHz reference clock and the frequency configuration word, and the first voltage-controlled oscillator outputs the corresponding point frequency signal respectively; when configured to work at the 10GHz point frequency, the 10GHz signal is filtered through the first channel of the first band-pass filter, and then sent into the fixed local oscillator power division and amplification unit through the first local oscillator switch circuit; when configured to work at the 24GHz point frequency, the 12GHz signal first enters the first frequency multiplier for 2 times frequency conversion to about 24GHz, and then the fundamental wave and the frequency multiplication harmonic are filtered out through the second channel of the first band-pass filter, and then sent into the fixed local oscillator power division and amplification unit through the first local oscillator switch circuit. The fixed local oscillator power division and amplification unit performs multi-stage amplification and power shaping on the selected point frequency local oscillator, and distributes the local oscillator signal into multiple fixed local oscillator outputs through the power division network, and the power of each output is not less than 16dBm, the fixed local oscillator spurious suppression degree is better than about 65dBc, the phase noise at 1kHz, 10kHz, 100kHz and 1MHz frequency offset is better than about -84dBc / Hz, -94dBc / Hz, -94dBc / Hz and -98dBc / Hz, and is used to provide two kinds of point frequency, local oscillator power sufficient and relatively pure spectrum driving signals for the external frequency conversion link.

[0058] In the frequency hopping local oscillator generation process, the second phase-locked synthesizer locks the second voltage-controlled oscillator in the first frequency range of 11GHz-21GHz under the same 100MHz reference clock and frequency configuration word control, and outputs multiple groups of frequency hopping radio frequency signals in 5MHz steps according to the frequency sequence given by the frequency configuration word; the second frequency multiplier performs 2 times frequency multiplication processing on the 11GHz-21GHz frequency hopping signal, expands the frequency to the second frequency range of 22GHz-42GHz, and the frequency step is correspondingly transformed into 10MHz, thereby meeting the frequency hopping local oscillator index requirements of 22GHz-42GHz and 10MHz steps; the frequency multiplication output accesses the segmented bandpass filter group, multiple bandpass filter channels are arranged inside the segmented bandpass filter group, the 22GHz-42GHz is divided into multiple sub-frequency bands, each bandpass channel corresponds to a sub-frequency band, and the control board controls the second local oscillator switch circuit and the segmented bandpass filter group to select the corresponding bandpass channel according to the sub-frequency band where the current target frequency hopping frequency point is located, only allows the frequency components in the target sub-frequency band to pass, and effectively suppresses the out-of-band frequencies and frequency multiplication harmonics; the 22GHz-42GHz frequency hopping local oscillator candidate signal output through the selected channel is sent to the frequency hopping local oscillator power division and amplification unit, and the frequency hopping local oscillator power division and amplification unit raises and distributes the frequency hopping local oscillator power into multiple outputs through multiple stages of amplification and power division network, the power of a single output is not less than 16dBm, the frequency hopping local oscillator spurious suppression degree is better than about 60dBc, the phase noise at a typical 28GHz frequency point can be better than about -84dBc / Hz, at 1kHz frequency offset, -98dBc / Hz at 1MHz frequency offset, the frequency hopping time is controlled to be about 220μs, not higher than 300μs, and the fast frequency hopping local oscillator output in a wide frequency band is realized.

[0059] In the state monitoring and alarm processing, the control board periodically accesses the internal state registers of the first phase-locked synthesizer and the second phase-locked synthesizer through the SPI interface, reads the locking state information of the fixed local oscillator board and the frequency hopping local oscillator board, and obtains the temperature information of the key positions inside the frequency synthesizer module through the temperature acquisition circuit register to form the state monitoring result; the state monitoring result is compared with the pre-set locking threshold and temperature threshold. The temperature acquisition circuit can be configured on the fixed local oscillator board, the frequency hopping local oscillator board or other related boards, and is used for real-time monitoring of the working temperature of the module. The temperature data read by the temperature acquisition circuit is used to judge the working state of the module.

[0060] The pre-set locking threshold and temperature threshold are configured by the control board and set according to the working requirements of the frequency synthesizer module, wherein the locking threshold is the maximum allowed error of the local oscillator locking (for example, ±5MHz), and the temperature threshold is the maximum allowed temperature of the key positions inside the module (for example, 85℃).

[0061] When the local oscillator locking indication is normal and the temperature monitoring value is within the allowable range, the working state of the fixed local oscillator board and the frequency hopping local oscillator board is determined as normal state; when the local oscillator locking has occasional loss of lock or the temperature is close to the upper limit of the preset temperature threshold, it is determined as reduced capacity state, and the output power can be adjusted or part of the working mode is limited to reduce the thermal load; when continuous loss of lock is monitored, the temperature exceeds the limit value or the external device requests to close the local oscillator output, the state monitoring result indicates the alarm state, the control board reissues the frequency configuration word and the working mode configuration word for reconfiguration, simultaneously outputs the alarm information through the external communication interface, and closes the enable channel of the fixed local oscillator power distribution amplifier unit and the frequency hopping local oscillator power distribution amplifier unit, so that the fixed local oscillator output end and the frequency hopping local oscillator output end enter the closed state, thereby preventing abnormal local oscillator signals from causing interference to the subsequent frequency conversion link and the measured device.

[0062] The embodiment generates the fixed point frequency local oscillator, generates the wideband frequency hopping local oscillator, shapes the multi-path output power, and monitors the running state and controls the alarm on the basis of the unified 100MHz high stability reference clock and the double-path phase-locked local oscillator link, realizes the complete working process control of the frequency synthesis module, and makes the frequency synthesis module meet the 24GHz / 10GHz point frequency and 22GHz-42GHz, 10MHz step frequency hopping index, has low phase noise, high spurious suppression, fast frequency hopping and monitorable running state, and is convenient for the whole system to realize stable and maintainable local oscillator resource management in complex working environment.

[0063] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application rather than limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application, and all of them should be covered in the scope of the claims of the present application.

Claims

1. A frequency synthesizer module, characterized by: The control board, the fixed local oscillator board, the frequency hopping local oscillator board, the power division clock board, the fixed local oscillator power division amplification unit and the frequency hopping local oscillator power division amplification unit are included. The control board includes a programmable logic device, a serial interface circuit and a voltage conversion circuit, the programmable logic device is connected with the first phase-locked synthesizer and the second phase-locked synthesizer through the serial interface circuit, and the voltage conversion circuit is connected with the fixed local oscillator board, the frequency hopping local oscillator board and the power division clock board. The output end of the fixed local oscillator power division amplification unit is used as a fixed local oscillator output end, and the output end of the frequency hopping local oscillator power division amplification unit is used as a frequency hopping local oscillator output end. The fixed local oscillator board includes a first phase-locked synthesizer, a first voltage-controlled oscillator, a first frequency multiplier and a first band-pass filter, and the output end of the first band-pass filter is connected with the input end of the fixed local oscillator power division amplification unit through a first local oscillator switch circuit. The frequency hopping local oscillator board includes a second phase-locked synthesizer, a second voltage-controlled oscillator, a second frequency multiplier and a segmented band-pass filter group connected in series, and the output end of the segmented band-pass filter group is connected with the input end of the frequency hopping local oscillator power division amplification unit through a second local oscillator switch circuit. The output frequency of the second voltage-controlled oscillator is adjusted at a fixed frequency interval in a first frequency range, the output frequency of the second frequency multiplier is adjusted at a corresponding frequency interval in a second frequency range, the segmented band-pass filter group includes a plurality of band-pass filter channels, and the plurality of band-pass filter channels correspond to a plurality of sub-frequency bands in the second frequency range respectively. The second voltage-controlled oscillator generates a plurality of groups of frequency hopping radio frequency signals according to a frequency sequence given by a frequency configuration word, the second frequency multiplier outputs a plurality of groups of frequency hopping local oscillator candidate signals, the segmented band-pass filter group selects a target band-pass filter channel in the plurality of band-pass filter channels, and the frequency hopping local oscillator power division amplification unit receives a frequency hopping local oscillator output signal from the target band-pass filter channel and provides a plurality of frequency hopping local oscillator output ends. The power division clock board includes a phase-locked crystal oscillator circuit and a clock power division network, the output end of the phase-locked crystal oscillator circuit is connected with the input end of the clock power division network, the first output end of the clock power division network is connected with the reference input end of the first phase-locked synthesizer, the second output end of the clock power division network is connected with the reference input end of the second phase-locked synthesizer, and at least one output end of the clock power division network is used as a frequency synthesizer module clock output end.

2. The frequency synthesizer module of claim 1, wherein: The first voltage-controlled oscillator in the fixed local oscillator board outputs at least two point frequency signals, one point frequency signal is output through a first channel of the first band-pass filter, and another point frequency signal is output through a second channel of the first band-pass filter and the first frequency multiplier. The first local oscillator switch circuit selects between the first channel output and the second channel output and connects the selected channel output to the input end of the fixed local oscillator power division amplification unit.

3. The frequency synthesizer module of claim 2 wherein: The programmable logic device communicates with the first phase-locked synthesizer and the second phase-locked synthesizer through a serial peripheral interface protocol, and the serial peripheral interface protocol includes a clock signal line, a chip selection signal line and a data line.

4. The frequency synthesizer module of claim 3 wherein: The first local oscillator switch circuit selects between the first fixed local oscillator frequency channel and the second fixed local oscillator frequency channel, and the fixed local oscillator power division amplification unit receives a fixed local oscillator output signal from the selected channel and provides a plurality of fixed local oscillator output ends.

5. The frequency synthesizer module of claim 4, wherein: The control board accesses the first phase-locked synthesizer and the second phase-locked synthesizer to read the state information, accesses the temperature acquisition circuit register to read the internal temperature information of the frequency synthesis module, and generates a state monitoring result.

6. The frequency synthesizer module of claim 5 wherein: The state monitoring result is compared with a threshold parameter to determine the working state of the fixed local oscillator board and the frequency hopping local oscillator board.

7. The frequency synthesizer module as described in claim 6, characterized in that: When the state monitoring result indicates an alarm state, the control board reissues a frequency configuration word and a working mode configuration word, outputs alarm information through an external communication interface, and closes the fixed local oscillator output end and the frequency hopping local oscillator output end.

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