阅读说明：本技术 一种基于恒温槽的锁相环输出信号相位稳定方法 (Phase-locked loop output signal phase stabilization method based on constant temperature bath ) 是由 侯照临 陈昌锐 张文锋 刘武广 唐晶晶 赵翔 于 2019-08-23 设计创作，主要内容包括：本发明涉及射频微波技术领域,公开了一种基于恒温槽的锁相环输出信号相位稳定方法。将恒温槽应用于锁相环,针对系统需求对锁相环及恒温槽设计要求进行细化,由系统需求的相位稳定度要求及锁相环相位温度敏感度确定恒温槽内温度达到恒温目标温度后的温度稳定度,并设计锁相环尺寸、重量、功耗等参数；将锁相环和恒温槽进行一体化集成。集成整体在加电工作后某确定时间内,恒温槽实现预期的温度稳定效果,锁相环在近似恒温的条件下工作,弱化环境温度对锁相环的影响,使锁相环输出信号相位达到一定的稳定状态。(the invention relates to the technical field of radio frequency microwaves and discloses a phase-locked loop output signal phase stabilization method based on a constant temperature bath. The constant temperature groove is applied to a phase-locked loop, design requirements of the phase-locked loop and the constant temperature groove are refined according to system requirements, the temperature stability after the temperature in the constant temperature groove reaches a constant temperature target temperature is determined according to phase stability requirements of the system requirements and phase temperature sensitivity of the phase-locked loop, and parameters such as size, weight and power consumption of the phase-locked loop are designed; and integrally integrating the phase-locked loop and the thermostatic bath. The integrated whole realizes the expected temperature stabilization effect in a certain determined time after power-on work, and the phase-locked loop works under the condition of approximate constant temperature, thereby weakening the influence of the environmental temperature on the phase-locked loop and leading the phase of the output signal of the phase-locked loop to reach a certain stable state.)

1. A phase stabilization method for phase-locked loop output signals based on a constant temperature slot is characterized by comprising the following steps:

Step S1, decomposing system requirements and determining a phase-locked loop design scheme;

step S2, designing a phase-locked loop and giving the phase temperature sensitivity of the phase-locked loop;

Step S3, determining the temperature stability after the temperature in the thermostatic bath reaches the constant temperature target temperature according to the phase stability requirement required by the system and the phase temperature sensitivity of the phase-locked loop;

Step S4, designing a phase-locked loop, and obtaining the size, the material and the weight of the phase-locked loop and the power consumption of the phase-locked loop through design statistics or tests;

step S5, determining the power supply and power consumption of the thermostatic bath according to the power supply required by the system and the power consumption of the phase-locked loop;

Step S6, determining the temperature change rate by the working environment condition, phase electrifying stabilization time and constant temperature target temperature of the integrated phase-locked loop and constant temperature tank;

Step S7, determining an integrated form of the phase-locked loop and the thermostatic bath;

step S8, determining the power supply and radio frequency signal transmission interface form to supply power to the phase-locked loop and thermostatic bath integrated body and realize radio frequency signal transmission;

Step S9, formulating a thermostatic bath design requirement, wherein the thermostatic bath design requirement comprises the elements obtained in the step S1 to the step S8, and the appearance requirement and the working environment condition of the integral structure of the thermostatic bath and the phase-locked loop integrated by the system;

Step S10, judging whether the design requirement of the thermostatic bath exceeds the design capability, if the design requirement exceeds the design capability, feeding back to the system requirement and the design of the phase-locked loop, and performing modification iteration; if the design capability is not exceeded, performing step S11;

Step S11, integrally integrating the phase-locked loop and the thermostatic bath according to the integrated form preset in the step S7;

step S12, testing the phase electrifying stabilization time and the phase stability of the integrated whole;

step S13, judging whether the test result meets the system requirement, and completing the task if the test result meets the system requirement; and if the system requirements are not met, modifying iteration is carried out, and the design of a phase-locked loop and a constant temperature bath is improved.

2. The method for phase stabilizing an output signal of an oven-controlled phase-locked loop as claimed in claim 1, wherein in step S1, the phase-locked loop is designed to: the five indexes of output frequency, harmonic suppression, spurious suppression, output power and phase noise required by the system are mapped into the phase-locked loop design, and the indexes must meet the system requirement within the working temperature range of the phase-locked loop.

3. the method for phase stabilizing an output signal of an oven-based phase-locked loop of claim 2, wherein in step S1, the phase-locked loop operating temperature range is determined by the normal operating temperature range of the device in the phase-locked loop design.

4. the method for phase stabilizing an output signal of an oven-based phase-locked loop of claim 1, wherein in step S2, the phase temperature sensitivity has different values at different temperature points within an operating range of the phase-locked loop.

5. The method for phase-stabilizing an output signal of a phase-locked loop based on an oven as claimed in claim 1, wherein in step S3, the temperature stability is characterized by an offset Δ T of the temperature in the oven relative to a constant temperature target temperature, and the following condition is satisfied:

S×|ΔT|≤|X|

The phase fluctuation is represented by Xpha, and the Xpha is given by system requirements; and the environment temperature of the phase-locked loop must be ensured not to exceed the working temperature range of the phase-locked loop all the time.

6. the method for phase stabilizing an output signal of an oven-based phase-locked loop of claim 1, wherein in step S5, a supply voltage of the oven is equal to a supply voltage required by a system, and a power consumption of the oven is less than or equal to a total supply power available by the system minus a power consumption of the phase-locked loop.

7. The method for phase stabilizing an output signal of an oven-based phase-locked loop of claim 1, wherein in step S6, the ramp rate satisfies:

t×(R-R)>ΔT

Wherein tsys is the phase power-on stabilization time required by the system; RT is the temperature change rate of the thermostatic bath, Rmar is the engineering allowance of the temperature change rate, and Delta Tc is the temperature value to be changed, and the calculation formula of the Delta Tc is as follows:

ΔT＝max{|T-T|,|T-T|}

Ta is a constant temperature target temperature which is selected within the working temperature range of the phase-locked loop, TH is a working environment temperature upper limit temperature value of the integrated phase-locked loop and thermostatic bath provided by the system, and TL is a working environment temperature lower limit temperature value of the integrated phase-locked loop and thermostatic bath provided by the system.

8. The method for phase stabilizing an output signal of an oven-controlled phase-locked loop according to claim 1, wherein in step S7, the phase-locked loop and the oven are integrated into a complete package or a partial package.

Technical Field

the invention relates to the technical field of radio frequency microwave, in particular to a phase-locked loop output signal phase stabilization method based on a constant temperature bath.

Background

The phase-locked loop is widely applied to radio frequency microwave circuits and systems. Through a large amount of experimental tests verification, the environmental temperature change has great influence on the phase of the phase-locked loop output signal, and the phase-locked loop output signal shows that: the phase of the output signal of the phase-locked loop may drift with ambient temperature changes. Meanwhile, the problem has certain discreteness, which shows that the influence degree of the phase of an output signal by temperature change is different among different individuals produced and processed by phase-locked loops with the same type design. In the prior system application, a certain time is needed after the system is powered on, the phase of the output signal of the phase-locked loop can enter a certain stable state only when the working environment of the phase-locked loop reaches a certain stable state, but once the temperature of the working environment changes, the phase of the output signal of the phase-locked loop can change along with the change. The problem is not concerned with a system with low phase requirement, but the influence of the problem on the system is obvious for the system application with high phase requirement; for a system working in a wide temperature area or under the condition of severe environmental temperature change, the phase drift problem of the output signal of the phase-locked loop is more prominent; especially for a distributed system applying a plurality of same-frequency phase-locked loops to different positions of the system, the phase of the output signal of each individual phase-locked loop cannot be in a certain stable state, which causes the disordered change of the phase relationship among the output signals of the plurality of same-frequency phase-locked loops, thus causing the deterioration of system indexes and even causing the system to be incapable of working normally.

The thermostatic bath has a few application directions in an electronic circuit, and is mainly applied to a thermostatic crystal oscillator circuit to solve the problem that the performance index of the crystal oscillator is easily influenced by temperature. For example, patent "crystal oscillator and temperature control circuit with thermostat (CN 201220224645)", patent "crystal oscillator with thermostat (CN 201710098206)", patent "a high-stability beacon source (CN 201310375017)", and the like all relate to the application of a thermostat to a crystal oscillator. The commonly applied method of the oven in the crystal oscillator is as follows: the crystal oscillator is arranged in a constant temperature bath, and the shell is used for carrying out integrated integration to work as a whole; a temperature sensor and a temperature control unit are arranged in the thermostatic bath for temperature control, so that the crystal oscillator works in a certain relatively constant temperature point environment to improve the index of the crystal oscillator.

The application of the constant temperature bath to the phase-locked loop is not available in the industry.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the existing problems, the constant temperature groove is applied to the phase-locked loop, the design requirements of the phase-locked loop and the constant temperature groove are refined according to the system requirements, the phase-locked loop and the constant temperature groove are integrated, the integrated whole realizes the expected temperature stabilization effect in a determined time after power-on work, the phase-locked loop works under the condition of approximate constant temperature, the influence of the environment temperature on the phase-locked loop is weakened, and the phase of the output signal of the phase-locked loop reaches a certain stable state.

The technical scheme adopted by the invention is as follows: a phase stabilization method for phase-locked loop output signals based on a constant temperature slot comprises the following steps:

step S1, decomposing system requirements and determining a phase-locked loop design scheme;

step S2, designing a phase-locked loop and giving the phase temperature sensitivity of the phase-locked loop;

Step S3, determining the temperature stability after the temperature in the thermostatic bath reaches the constant temperature target temperature according to the phase stability requirement required by the system and the phase temperature sensitivity of the phase-locked loop;

step S4, designing a phase-locked loop, and obtaining the size of the phase-locked loop structure, the material and weight of the phase-locked loop and the power consumption (represented by Ppll) of the phase-locked loop through design statistics or tests;

Step S5, determining the power supply and power consumption of the thermostatic bath according to the power supply required by the system and the power consumption of the phase-locked loop;

Step S6, determining the temperature change rate by the working environment condition, phase electrifying stabilization time and constant temperature target temperature of the integrated phase-locked loop and constant temperature tank;

Step S7, determining an integrated form of the phase-locked loop and the thermostatic bath;

step S8, determining the power supply and radio frequency signal transmission interface form to supply power to the phase-locked loop and thermostatic bath integrated body and realize radio frequency signal transmission;

step S9, formulating a thermostatic bath design requirement, wherein the thermostatic bath design requirement comprises the elements obtained in the step S1 to the step S8, and the appearance requirement and the working environment condition of the integral structure of the thermostatic bath and the phase-locked loop integrated by the system;

step S10, judging whether the design requirement of the thermostatic bath exceeds the design capability, if the design requirement exceeds the design capability, feeding back to the system requirement and the design of the phase-locked loop, and performing modification iteration; if the design capability is not exceeded, performing step S11;

step S11, integrally integrating the phase-locked loop and the thermostatic bath according to the integrated form preset in the step S7;

Step S12, testing the phase electrifying stabilization time and the phase stability of the integrated whole;

step S13, judging whether the test result meets the system requirement, and completing the task if the test result meets the system requirement; and if the system requirements are not met, modifying iteration is carried out, and the design of a phase-locked loop and a constant temperature bath is improved.

Further, in step S1, the phase-locked loop is designed as follows: the five indexes of output frequency, harmonic suppression, spurious suppression, output power and phase noise required by the system are mapped into the phase-locked loop design, and the indexes must meet the system requirement within the working temperature range of the phase-locked loop.

further, in the step S1, the operating temperature range of the phase-locked loop is determined by the design of the phase-locked loop, the operating temperature range of the phase-locked loop is determined by the normal operating temperature range of the device in the design of the phase-locked loop, and the constant temperature target temperature is selected within the operating temperature range of the phase-locked loop; the formula is expressed as:

ta e (T1, T2) (formula 1)

ta is the target constant temperature which is expected to be achieved in the constant temperature tank, T1 is the lower temperature limit of the phase-locked loop which can work normally, and T2 is the upper temperature limit of the phase-locked loop which can work normally.

further, in the step S2, the phase temperature sensitivity has different values at different temperature points within the operating range of the phase-locked loop; in engineering implementation, aiming at the constant temperature target temperature Ta, an approximate value can be simply used for representing phase temperature sensitivity; the formula is expressed as:

Sha @ Ta (formula 2)

and defines Sha ∈ [0,360 ].

Further, in step S3, the temperature stability is represented by an offset Δ T of the temperature in the thermostatic bath with respect to the constant temperature target temperature, and the following condition is satisfied:

Sha X| DeltaT | ≦ | Xpha | (equation 3)

wherein Sha is introduced from formula 2, Delta T is the offset of the temperature in the constant temperature tank relative to the constant temperature target temperature, Xpha is the maximum allowable offset of the phase of the output signal of the phase-locked loop relative to the stable phase, representing the phase fluctuation, and Xpha is given by the system requirement; and must ensure that:

Ta + DeltaT ∈ [ T1, T2] (formula 4)

Namely, the environment temperature of the phase-locked loop can not exceed the working temperature range of the phase-locked loop all the time.

further, in step S5, the power supply voltage of the thermostat is equal to the power supply voltage required by the system, and the power consumption of the thermostat is less than or equal to the total power supply available by the system minus the power consumption of the phase-locked loop, which is expressed by the following formula:

vinc Vsys (equation 5)

pinc ≦ Psys-Ppll (equation 6)

Wherein Vinc is the supply voltage of the thermostatic bath, and Vsys is the supply voltage required by the system; pinc is the power consumption of the thermostatic bath, Psys is the total power supply power which can be provided for the phase-locked loop and the thermostatic bath by the system, and Ppll is the power consumption of the phase-locked loop.

Further, in step S6, the temperature change rate satisfies:

tsys × (RT-Rmar) > Δ Tc (equation 7)

wherein tsys is the phase power-on stabilization time required by the system; RT is the temperature changing rate of the thermostatic bath, Rmar is the engineering margin of the temperature changing rate, and Δ Tc is the temperature magnitude value to be changed, wherein Δ Tc is determined by the formula 8:

Δ Tc { | Ta-TH |, | Ta-TL | } (equation 8)

Ta is introduced from formula 1, TH is the working environment temperature upper limit temperature value of the integrated phase-locked loop and thermostatic bath provided by the system, TL is the working environment temperature lower limit temperature value of the integrated phase-locked loop and thermostatic bath provided by the system

further, in the step S7, the phase-locked loop and the oven cavity may be integrated in a fully wrapped form (i.e., the phase-locked loop is completely disposed in the oven cavity) or in a partially wrapped form (i.e., the oven cavity does not form a complete wrapping on the phase-locked loop).

compared with the prior art, the beneficial effects of adopting the technical scheme are as follows: by adopting the technical scheme of the invention, the working temperature of the phase-locked loop can be limited within a certain range within a certain determined time by utilizing the temperature control capability of the thermostatic bath, and the influence of the environmental temperature and the change thereof on the phase of the output signal of the phase-locked loop is weakened, so that the phase of the output signal of the phase-locked loop reaches a certain stable state.

drawings

fig. 1 is a flow chart of a method for phase stabilization of an output signal of a constant temperature slot-based phase-locked loop.

fig. 2 is a schematic diagram of an integrated form.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

In a certain system, a high-stability reference source and a phase-locked loop are used for frequency synthesis, and in order to realize the system target, the following requirements are put forward on a certain type of phase-locked loop: the phase difference, namely the offset of the phase-locked loop output signal relative to the phase of a standard signal (stable phase), is required to be stabilized within +/-3 degrees of the baseline in the process from 20 minutes of power-on work to 6 hours of power-on work. The index is examined at the room temperature of 20-25 ℃, and simultaneously, the design ensures that the index can be realized in a temperature region of-40 ℃ to +65 ℃.

The phase-locked loop and the reference signal of the signal source are from the passive power division signal of the high-stability reference source, and the influence of the reference signal on the phase difference change can be eliminated. The key point is that the phase of the output signal of the phase-locked loop reaches and keeps a certain stable state within 20 minutes of the power-on operation, so that the phase of the output signal of the phase-locked loop is ensured to be stabilized within the system requirement range in the process from 20 minutes of the power-on operation to 6 hours of the power-on operation.

To verify the effectiveness of the method described in the present invention, a network analyzer (here, KEYSIGHT corporation N5242A PNA-X microwave network analyzer) and a signal source (here, KEYSIGHT corporation E8257D PSG analog signal generator) were used to set up a test system. The signal source and the phase-locked loop adopt passive power division signals from the same high-stability reference source as reference signals and output signals with the same frequency. And the signal source enters a stable working state after being electrified and preheated, and the output signal of the signal source is used as a standard. The phase stability of the output signal of the phase-locked loop is measured by measuring the phase difference change between the standard signal and the output signal of the phase-locked loop by using the phase difference measuring function of the network analyzer.

Phase-locked loop a (output frequency 4.5GHz) was selected and the test was performed without the method described in the present invention. Under the condition of room temperature of 20-25 ℃, the phase difference between the output signal of the phase-locked loop A and the standard signal is measured to be about 12.5 degrees when the phase-locked loop A is electrified and works for 20 minutes. And continuously monitoring, and detecting that the phase difference is in a change state, wherein the phase difference of the output signals of the two phase-locked loops is about-159 ℃ when the two phase-locked loops are electrified and work for 2 hours. In the process from 20 minutes to 2 hours, the phase difference change between the two signals is close to-170 degrees, and obviously, the system requirements cannot be met.

the method for stabilizing the phase of the output signal of the phase-locked loop based on the constant temperature tank, which is described in the patent, is carried out according to the implementation steps shown in fig. 1.

1) And analyzing system requirements and determining a phase-locked loop design scheme. The selected phase-locked loop A meets the system requirements in the aspects of indexes such as output frequency, harmonic suppression, stray suppression, output power, phase noise and the like, and can normally work within the working temperature range of the phase-locked loop from minus 55 ℃ to plus 85 ℃.

2) designing a phase-locked loop: the phase-locked loop A is selected to complete the design work, and the phase temperature sensitivity of the phase-locked loop A is obtained by a testing means to be about 3.5 degrees/DEG C @75 ℃.

3) and acquiring design requirement elements of the thermostatic bath based on system requirements and a phase-locked loop scheme. The method comprises the following steps:

a) the working temperature range (-55 ℃ to +85 ℃) of the phase-locked loop obtained in the step 1) is combined with the design capability of the thermostatic bath, and +75 ℃ is selected as the constant temperature target temperature Ta in the index requirement of the thermostatic bath;

b) The phase temperature sensitivity (about 3.5 degrees/DEG C @75 ℃) of the phase-locked loop A and the system requirement that the phase stability is within +/-3 degrees are considered, and certain engineering allowance is considered, and | delta T | is required to be less than or equal to 0.5 ℃;

c) providing the structural size, the bill of materials and the weight (15g) of the phase-locked loop and the power consumption (about 1W) of the phase-locked loop;

d) Comprehensively analyzing the power supply in the system requirement and the power consumption of the phase-locked loop, wherein the system can provide +5V/800mA power supply, the phase-locked loop needs +5V/200mA power supply, and the rest +5V/600mA power supply can be used by a constant temperature bath;

e) the working temperature range is-40 ℃ to +65 ℃ (system requirement), and the temperature change rate of 5.75 ℃/min is ensured when the temperature reaches about +75 ℃ within 20 min (under the condition of the lowest working temperature of-40 ℃ to +75 ℃ according to the system requirement). In engineering application, the temperature change rate of the thermostatic bath and the engineering allowance of the temperature change rate of the thermostatic bath are improved as much as possible on the premise of realization, and the thermostatic bath is required to meet the temperature change rate of 8 ℃/min;

f) as shown in fig. 2(a), a complete wrapping form is selected as an integrated form of the phase-locked loop and the oven, and the present invention is not limited to the complete wrapping form of this embodiment, and the present invention may also adopt the partial wrapping form of fig. 2(b) and the partial wrapping form of fig. 2(c) with a very low wrapping degree;

g) The power supply is introduced in an insulator welding mode; the reference signal is input by an SMA radio frequency interface, and the output signal is output by the SMA radio frequency interface;

h) Comprehensively analyzing the system requirements and the structure and interface requirements of the phase-locked loop, and converting the system requirements and the structure and interface requirements into the structure and interface in the index requirements of the thermostatic bath; the system requires that the integral size after the integration is not more than 80mm by 25 mm; the fixing mode is screw fixation;

i) providing the integral working environment temperature range of minus 40 ℃ to plus 65 ℃ after the phase-locked loop required by the system and the thermostatic bath are integrated;

4) Judging that the index requirement of the thermostatic bath does not exceed the design capability, and performing step 5);

5) designing a constant temperature tank;

6) The phase-locked loop A and the thermostatic bath are integrated in an integrated mode, the embodiment adopts a complete wrapping mode to integrate, the thermostatic bath is provided with a metal shell containing a heat insulation layer to form a closed structure, and the phase-locked loop PCB is attached in the thermostatic bath;

7) And carrying out phase electrifying stability time and phase stability test on the integrated whole.

and carrying out testing after integrating the phase-locked loop A and the thermostatic bath. And under the condition of room temperature of 20-25 ℃, the integrated whole is electrified for 20 minutes and then is tested, and the phase difference between the output signal of the phase-locked loop A and the standard signal output by the signal source is measured to be about-130 ℃. The phase difference is continuously monitored and is in a slowly changing state until the phase difference is measured to be about-131.5 degrees after the phase difference is electrified and operated for 7 hours. The phase difference change is within-1.5 degrees in the process of electrifying for 20 minutes to 7 minutes, and the system requirement of a baseline within +/-3 degrees is met.

8) And the test result meets the system requirement and completes the task.

the verification of the above example shows that the phase stabilization method of the phase-locked loop output signal based on the constant temperature bath is effective.

the invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed. Those skilled in the art to which the invention pertains will appreciate that insubstantial changes or modifications can be made without departing from the spirit of the invention as defined by the appended claims.