A common delay line and an optical phase-locked loop link device for simultaneous phase locking of dual chirp signals

Abstract

The present invention provides a common delay line and an optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals, comprising an upper and a lower swept frequency modulated continuous wave source, a common Mach-Zehnder interferometer module, an optical quadrature front end, and an optical phase-locked loop module; the upper and lower swept frequency modulated continuous wave sources use triangular waves with opposite phases for modulation to generate an upper swept frequency modulated continuous wave source and a lower swept frequency modulated continuous wave source, and output dual chirp signals within half a modulation period; the common Mach-Zehnder interferometer module is arranged on the optical path, receives the dual chirp signals, and outputs them. The present invention can improve the phase noise correlation between the two chirp sources, suppress the phase noise of each of the two chirp sources, improve the linearity of the chirp, and the device can also improve the utilization efficiency of the delay line and enhance the device integration of the entire optical module and electrical module.

Description

Technical Field

[0001] The present invention belongs to the technical field of digital signal processing, and particularly relates to a common delay line and an optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals. Background Art

[0002] Frequency-modulated continuous-wave lidar has been widely used in the fields of autonomous driving, assisted navigation, car accident warning, etc. due to its characteristics of high sensitivity, high precision, low power consumption, eye safety, anti-stray light interference, and simultaneous mapping of object distance / velocity information. Obtaining the distance / velocity information of the object to be measured simultaneously requires the frequency-modulated continuous-wave signal to have up and down chirps. Currently, the generation schemes for dual chirps mainly include triangular wave modulation distributed feedback semiconductor lasers, external modulation schemes based on carrier suppression technology, etc. The former can obtain up and down chirps within one modulation period, but the acquisition time of the distance / velocity information needs to be greater than one modulation period, which greatly limits the performance of this scheme in scenarios such as car accident warning that require fast response times. The latter can generate up and down chirp signals simultaneously within half a modulation period through carrier suppression technology, but this scheme requires the use of expensive modulators. At the same time, the bias point of the modulator will be interfered by environmental factors, and the sweep bandwidth will also be limited by the bandwidth of the modulator.

[0003] In addition to the above two schemes for generating dual chirps, two distributed feedback semiconductor lasers with similar wavelengths can also be used, and voltage signals with opposite scanning directions are used for driving. Subsequently, the outputs of the two chirp sources are coupled to obtain a dual chirp source. However, this scheme currently has key problems such as poor phase noise correlation between the two chirps, large phase noise of each of the two chirp sources, poor chirp linearity, and inability to use a consistent pre-distortion waveform for correction. Summary of the Invention

[0004] The purpose of the present invention is to solve the defects existing in the above-mentioned prior art, and provide a common delay line and an optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals.

[0005] The present invention adopts the following technical solutions:

[0006] A common delay line and an optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals, including up and down sweep frequency-modulated continuous-wave sources, a common Mach-Zehnder interferometer module, an optical quadrature front end, and an optical phase-locked loop module.

[0007] The up and down sweep frequency-modulated continuous-wave sources are modulated by triangular waves with opposite phases to generate an up sweep frequency-modulated continuous-wave source and a down sweep frequency-modulated continuous-wave source, and output dual chirp signals within half a period.

[0008] A shared Mach-Zehnder interferometer module is arranged on the optical path to receive the double-chirp signal and output it.

[0009] An optical quadrature front end receives the output of the shared Mach-Zehnder interferometer module, extracts the beat frequency electrical signal, and outputs it.

[0010] An optical phase-locked loop module is electrically connected to the optical quadrature front end and the up- and down-sweeping frequency-modulated continuous wave sources. It receives the beat frequency electrical signal output by the optical quadrature front end and feeds the signal back to the up- and down-sweeping frequency-modulated continuous wave sources to achieve simultaneous phase locking.

[0011] In one embodiment, the shared Mach-Zehnder interferometer module includes a Mach-Zehnder interferometer module I, a Mach-Zehnder interferometer module II, and a shared optical fiber delay line.

[0012] The Mach-Zehnder interferometer I and the Mach-Zehnder interferometer II are placed in parallel.

[0013] The Mach-Zehnder interferometer I receives the chirp signal from the up-sweeping frequency-modulated continuous wave source and outputs it.

[0014] The Mach-Zehnder interferometer II receives the chirp signal from the down-sweeping frequency-modulated continuous wave source and outputs it.

[0015] The shared optical fiber delay line combines the signals received by the Mach-Zehnder interferometer I and the Mach-Zehnder interferometer II and then outputs them.

[0016] In one embodiment, the optical phase-locked loop module includes a mixer, an electrical amplifier, an integrator, and an arbitrary function generator.

[0017] The arbitrary function generator generates a reference signal and transmits the signal to mixer I and mixer II.

[0018] The mixer includes mixer I and mixer II.

[0019] Mixer I mixes the reference signal with the beat frequency electrical signal output by the optical quadrature front end to generate an error signal.

[0020] Mixer II mixes the reference signal with the beat frequency electrical signal output by the optical quadrature front end to generate an error signal.

[0021] The electrical amplifier includes electrical amplifier I and electrical amplifier II.

[0022] Electrical amplifier I receives the error signal generated by mixer I, amplifies it, and then outputs it.

[0023] Electrical amplifier II receives the error signal generated by mixer II, amplifies it, and then outputs it.

[0024] The integrator includes integrator I and integrator II.

[0025] Integrator I receives the error signal processed by Electric Amplifier I, integrates it, and outputs the result to the upward-sweeping frequency-modulated continuous wave source.

[0026] Integrator II receives the error signal processed by Electric Amplifier II, integrates it, and outputs the result to the downward-sweeping frequency-modulated continuous wave source.

[0027] In one embodiment, the upward- and downward-sweeping frequency-modulated continuous wave sources are generated by two independent current-modulated distributed feedback semiconductor lasers.

[0028] In one embodiment, both Mach-Zehnder Interferometer I and Mach-Zehnder Interferometer II are composed of two 5:5 fiber-optic couplers connected in series. The fiber-optic coupler is used for optical signal coupling, outputs the signal to the common fiber-optic delay line, and is also used for result output. The length of the common fiber-optic delay line is 10 m.

[0029] In one embodiment, the optical quadrature front end includes a 90° optical phase shifter and two balanced detectors. After the two optical signals pass through the optical quadrature front end, electrical beat signals with a 90° phase difference are output.

[0030] In one embodiment, the electrical signal output by the arbitrary function generator has a phase noise of -125 dBc / Hz@10 kHz within the frequency range of 0.1 kHz - 10 MHz. Electric Amplifier I and Electric Amplifier II are the same devices and can provide an adjustable amplification / attenuation factor of 60 dB. The integration time of the integrator is 0.1 ms, which is designed by the resistor-capacitor time constant.

[0031] Advantages of the present invention:

[0032] The present invention provides a dual-chirp linear sweep source. In the entire device, the output power of the laser for generating the upward-sweeping frequency-modulated continuous wave is 57.83 mW, and the output power of the laser for generating the downward-sweeping frequency-modulated continuous wave is 60.00 mW. The operating temperature of this module is 20 °C. After beam splitting and beam combining, the output power of the finally phase-locked dual-chirp signal is 53 mW.

[0033] The coherence enhancement between incoherent sources is achieved by using a common phase-locked loop module, and the simultaneous phase locking of the dual-chirp is realized by using a common delay line, which improves the utilization efficiency of the delay line and enhances the device integration of the entire optical module and electrical module. Description of the Drawings

[0034] Figure 1 It is a structural schematic diagram of the present invention;

[0035] Figure 2Time-frequency analysis diagram after phase locking of the upward-sweeping frequency-modulated continuous wave source and the downward-sweeping frequency-modulated continuous wave source in Embodiment 1, where (a) is the time-frequency analysis diagram of the upward-sweeping frequency-modulated continuous wave source and (b) is the time-frequency analysis diagram of the downward-sweeping frequency-modulated continuous wave source.

[0036] Figure 3 Bar chart of the difference between the time-frequency signals output by the upward-sweeping frequency-modulated continuous wave source and the downward-sweeping frequency-modulated continuous wave source and the first-order fitting function, where (a) is the bar chart of the difference of the upward-sweeping frequency-modulated continuous wave source and (b) is the bar chart of the difference of the downward-sweeping frequency-modulated continuous wave source.

[0037] Figure 4 Comparison diagram of the error time series of the difference between the time-frequency signals output by the upward-sweeping frequency-modulated continuous wave source and the downward-sweeping frequency-modulated continuous wave source and the first-order fitting function.

[0038] Figure 5 Frequency noise power spectral density diagram of the difference between the time-frequency signals output by the upward-sweeping frequency-modulated continuous wave source and the downward-sweeping frequency-modulated continuous wave source and the first-order fitting function, where (a) is the upper chirp difference frequency noise power spectral density diagram of the upward-sweeping and downward-sweeping frequency-modulated continuous wave sources, and (b) is the lower chirp difference frequency noise power spectral density diagram of the upward-sweeping and downward-sweeping frequency-modulated continuous wave sources.

[0039] In the figure: 1 - upward and downward sweeping frequency-modulated continuous wave sources, 2 - shared Mach-Zehnder interferometer module, 3 - shared optical fiber delay line, 4 - optical quadrature front end, 5 - mixer, 6 - electrical amplifier, 7 - integrator, 8 - arbitrary function generator.

[0040] 1011 - upward-sweeping frequency-modulated continuous wave source, 1012 - downward-sweeping frequency-modulated continuous wave source.

[0041] 2021 - Mach-Zehnder interferometer Ⅰ, 2022 - Mach-Zehnder interferometer Ⅱ.

[0042] 5011 - mixer Ⅰ, 5012 - mixer Ⅱ.

[0043] 6011 - electrical amplifier Ⅰ, 6012 - electrical amplifier Ⅱ.

[0044] 7011 - integrator Ⅰ, 7012 - integrator Ⅱ.

[0045] Note: Up FMCW Source (Up sweep Frequency-Modulated Continuous-Wave Source), Down FMCW Source (Down sweep Frequency-Modulated Continuous-Wave Source), Fiber Optic Patch Cord (Fiber), Fiber Optic Coupler (FC), Fiber Optic Delay Line (DL, Delay-Line), 90° Hybrid, Mixer, Arbitrary Function Generator (AFG), Electrical Amplifier (AMP, Amplifier), Integrator. Detailed Implementation Manner

[0046] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0047] As Figure 1 shown, a common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals according to the present invention includes up and down sweep frequency-modulated continuous wave sources 1, a common Mach-Zehnder interferometer module 2, an optical quadrature front end 4, and an optical phase-locked loop module.

[0048] The up and down sweep frequency-modulated continuous wave sources 1 are modulated using triangular waves with opposite phases to generate an up sweep frequency-modulated continuous wave source 1011 and a down sweep frequency-modulated continuous wave source 1012, and output dual chirp signals within half a modulation period.

[0049] The common Mach-Zehnder interferometer module 2 is arranged on the optical path, receives the dual chirp signals, and outputs them.

[0050] The common Mach-Zehnder interferometer module 2 includes Mach-Zehnder interferometer I 2021, Mach-Zehnder interferometer II 2022, and a common fiber optic delay line 3.

[0051] Mach-Zehnder interferometer I 2021 is placed parallel to Mach-Zehnder interferometer II 2022.

[0052] Mach-Zehnder interferometer I 2021 receives the chirp signal of the up sweep frequency-modulated continuous wave source 1011 and outputs it.

[0053] Mach-Zehnder interferometer Ⅱ in 2022 receives the chirp signal of the down-sweeping continuous wave source 1012 and outputs it.

[0054] The shared optical fiber delay line 3 combines the double chirp signals received by the Mach-Zehnder interferometer Ⅰ 2021 and the Mach-Zehnder interferometer Ⅱ 2022 and then outputs them.

[0055] The optical quadrature front end 4 receives the output of the shared optical fiber delay line 3, extracts the beat frequency electrical signal, and outputs it to the mixer 5.

[0056] The optical phase-locked loop module is electrically connected to the optical quadrature front end 4 and the up and down sweeping frequency-modulated continuous wave sources 1. It receives the beat frequency electrical signal output by the optical quadrature front end 4 and feeds the signal back to the up and down sweeping frequency-modulated continuous wave sources 1 to achieve simultaneous phase locking.

[0057] The optical phase-locked loop module includes a mixer 5, an electrical amplifier 6, an integrator 7, and an arbitrary function generator 8.

[0058] The arbitrary function generator 8 generates a reference signal and transmits the signal to the mixer Ⅰ 5011 and the mixer Ⅱ 5012. The arbitrary function generator 8 can calculate a standard frequency according to the frequency sweep width of the frequency-modulated continuous wave and the length of the shared delay line. This frequency and the beat frequency output via the optical quadrature front end 4 mix out an error signal in the mixer 5.

[0059] The mixer 5 receives the reference signal generated by the arbitrary function generator 8 and the beat frequency electrical signal generated by the optical quadrature front end 4, and mixes the reference signal and the beat frequency signal to generate an error signal.

[0060] The mixer 5 includes a mixer Ⅰ 5011 and a mixer Ⅱ 5012.

[0061] The mixer Ⅰ 5011 mixes the reference signal with the beat frequency electrical signal output by the optical quadrature front end 4 to generate an error signal.

[0062] The mixer Ⅱ 5012 mixes the reference signal with the beat frequency electrical signal output by the optical quadrature front end 4 to generate an error signal.

[0063] The electrical amplifier 6 receives the error signal generated by the mixer 5, amplifies it, and then outputs it.

[0064] The electrical amplifier 6 includes an electrical amplifier Ⅰ 6011 and an electrical amplifier Ⅱ 6012.

[0065] The electrical amplifier Ⅰ 6011 receives the error signal generated by the mixer Ⅰ 5011, amplifies it, and then outputs it. The electrical amplifier Ⅰ 6011 is used to adjust the gain within the phase-locked loop formed by the up-sweeping frequency-modulated continuous wave source 1011.

[0066] The electrical amplifier II 6012 receives the error signal generated by the mixer II 5012, amplifies it, and then outputs it. The electrical amplifier II 6012 is used to adjust the gain within the phase-locked loop formed by the down-sweeping continuous wave source.

[0067] The integrator 7 receives the error signal amplified by the electrical amplifier 6, integrates it, and then outputs it to the up and down sweep frequency modulated continuous wave sources 1 to achieve simultaneous phase locking. The integrator 7 is used to accumulate the error information in the time domain. The integration time of the integrator 7 is 0.1 ms, and this integration time is designed by the resistor-capacitor time constant.

[0068] The integrator 7 includes an integrator I 7011 and an integrator II 7012.

[0069] The integrator I 7011 receives the error signal amplified by the electrical amplifier 6011, integrates it, and then outputs it to the up sweep frequency modulated continuous wave source 1011.

[0070] The integrator II 7012 receives the error signal amplified by the electrical amplifier 6012, integrates it, and then outputs it to the down sweep frequency modulated continuous wave source 1012.

[0071] In one embodiment, the up and down sweep frequency modulated continuous wave sources 1 are generated by two independent current-modulated distributed feedback semiconductor lasers.

[0072] In one embodiment, both the Mach-Zehnder interferometer I 2021 and the Mach-Zehnder interferometer II 2022 are composed of two 5:5 fiber optic couplers connected in series. The fiber optic coupler is used for optical signal coupling, outputs to the common fiber optic delay line 3, and is also used for result output. The length of the common fiber optic delay line 3 is 10 m.

[0073] In one embodiment, the optical quadrature front end 4 includes a 90° optical phase shifter and two balanced detectors. After two optical signals pass through the optical quadrature front end 4, they output electrical beat signals with a 90° phase difference. In the present invention, only the in-phase electrical signal output by the optical quadrature front end 4 is used, and the other orthogonal signal can be reserved for the acquisition signal path or other optimized algorithm interfaces.

[0074] In one embodiment, the phase noise of the electrical signal output by the arbitrary function generator 8 is -125 dBc / Hz@10 kHz within the frequency range of 0.1 kHz - 10 MHz. The electrical amplifier I 6011 and the electrical amplifier II 6012 are the same devices and can provide an adjustable amplification / attenuation multiple of 60 dB.

[0075] Embodiment

[0076] The peak-to-peak value of the modulation signal of the up and down sweep frequency modulated continuous wave sources 1 is 20 mA, and the modulation frequency is 2.5 kHz. The output power of the two frequency modulated continuous wave sources is approximately 60 mW, and the operating temperature is 20 °C.

[0077] The upper and lower sweep frequency-modulated continuous wave sources 1 are input into the shared Mach-Zehnder interferometer module 2 through fiber optic jumpers, and are combined on one arm of the shared fiber optic delay line 3 as the output. Thereafter, the signal enters the corresponding optical quadrature front end 4 to extract the beat frequency signal, and the respective beat frequency signals are fed back to the upper and lower sweep frequency-modulated continuous wave sources 1 through the optical phase-locked loop module to achieve simultaneous phase locking.

[0078] The results of the embodiments are tested respectively:

[0079] As Figure 2 shown, the result is obtained by using a single-frequency narrow linewidth laser to beat with the upper and lower frequency-modulated continuous wave sources, collecting the time series on an oscilloscope and using the short-time Fourier algorithm. It can be seen from the figure that the upper sweep frequency-modulated continuous wave source and the lower sweep frequency-modulated continuous wave source have good linearity, and there is a certain phase delay between them.

[0080] Statistical characterization is adopted:

[0081] As Figure 3 shown, the result is obtained by using an oscilloscope and a post-processing algorithm. The beat frequency signal from the optical quadrature front end 4 is collected by the oscilloscope. The post-processing process includes performing a Hilbert transform on the beat frequency signal to extract the upper and lower sweep frequency sequences, linearly fitting the frequency sequence and plotting the error bar statistics after subtracting the linearity. It can be seen from the figure that both the upper chirp and the lower chirp have similar residual distributions. Therefore, it can be known that the quality of the upper sweep frequency-modulated continuous wave source and the lower sweep frequency-modulated continuous wave source is almost the same, proving that there is a certain phase noise correlation between them.

[0082] Temporal sequence characterization is adopted:

[0083] As Figure 4 shown, the result is obtained by using an oscilloscope and a post-processing algorithm. The beat frequency signal from the optical quadrature front end 4 is collected by the oscilloscope. The post-processing process includes performing a Hilbert transform on the beat frequency signal to extract the upper and lower sweep frequency sequences, linearly fitting the frequency sequence and plotting the frequency sequence after subtracting the linear fit. It can be seen from the figure that both the upper chirp and the lower chirp have similar temporal sequence trends. Therefore, it can be known that the quality of the upper sweep frequency-modulated continuous wave source and the lower sweep frequency-modulated continuous wave source is almost the same, proving that there is a certain phase noise correlation between them.

[0084] Frequency characterization is adopted:

[0085] As Figure 5As shown, the result is obtained by using an oscilloscope and a post-processing algorithm. The oscilloscope is used to collect the beat signal from the optical quadrature front end. The post-processing process includes performing a Hilbert transform on the beat signal to extract the upper and lower sweep frequency sequences, linearly fitting the frequency sequence and obtaining the frequency sequence after subtracting the linear fit, and calculating the frequency noise power spectral density of the remaining frequency sequence. It can be seen from the figure that both the up-chirp and the down-chirp have similar frequency noise power spectral density distributions. Therefore, it can be known that the quality of the up-swept frequency modulated continuous wave source and the down-swept frequency modulated continuous wave source is almost the same, which proves that there is a certain phase noise correlation between them.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual-chirp signals, characterized in that , including up - and - down - sweeping frequency - modulated continuous - wave sources, a shared Mach - Zehnder interferometer module, an optical quadrature front - end, and an optical phase - locked loop module; The up - and - down - sweeping frequency - modulated continuous - wave sources use triangular waves with opposite phases for modulation to generate an up - sweeping frequency - modulated continuous - wave source and a down - sweeping frequency - modulated continuous - wave source, and output dual - chirp signals within half a modulation period; The shared Mach - Zehnder interferometer module is arranged on the optical path, receives the dual - chirp signals, and outputs them; The optical quadrature front - end receives the output of the shared Mach - Zehnder interferometer module, extracts the beat - frequency electrical signal, and outputs it; The optical phase - locked loop module is electrically connected to the optical quadrature front - end and the up - and - down - sweeping frequency - modulated continuous - wave sources, receives the beat - frequency electrical signal output by the optical quadrature front - end, and feeds the signals back to the up - and - down - sweeping frequency - modulated continuous - wave sources respectively to achieve simultaneous phase - locking; Among them, the shared Mach - Zehnder interferometer module includes Mach - Zehnder interferometer module Ⅰ, Mach - Zehnder interferometer module Ⅱ, and a shared optical fiber delay line; Mach - Zehnder interferometer Ⅰ and Mach - Zehnder interferometer Ⅱ are placed in parallel; Mach - Zehnder interferometer Ⅰ receives the chirp signal of the up - sweeping frequency - modulated continuous - wave source and outputs it; Mach - Zehnder interferometer Ⅱ receives the chirp signal of the down - sweeping frequency - modulated continuous - wave source and outputs it; The shared optical fiber delay line combines the signals received by Mach - Zehnder interferometer Ⅰ and Mach - Zehnder interferometer Ⅱ and then outputs them.

2. The common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals according to claim 1, wherein The optical phase - locked loop module includes a mixer, an electrical amplifier, an integrator, and an arbitrary function generator; The arbitrary function generator generates a reference signal and transmits the signal to mixer Ⅰ and mixer Ⅱ; The mixer includes mixer Ⅰ and mixer Ⅱ; Mixer Ⅰ mixes the reference signal with the beat - frequency electrical signal output by the optical quadrature front - end to generate an error signal; Mixer Ⅱ mixes the reference signal with the beat - frequency electrical signal output by the optical quadrature front - end to generate an error signal; The electrical amplifier includes electrical amplifier Ⅰ and electrical amplifier Ⅱ; Electrical amplifier Ⅰ receives the error signal generated by mixer Ⅰ, amplifies it, and then outputs it; Electrical amplifier Ⅱ receives the error signal generated by mixer Ⅱ, amplifies it, and then outputs it; The integrator includes integrator Ⅰ and integrator Ⅱ; Integrator Ⅰ receives the error signal amplified by electrical amplifier Ⅰ, integrates it, and then outputs it to the up - sweeping frequency - modulated continuous - wave source; Integrator Ⅱ receives the error signal amplified by electrical amplifier Ⅱ, integrates it, and then outputs it to the down - sweeping frequency - modulated continuous - wave source.

3. The common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual-chirp signals according to claim 1, characterized in that, The up - and - down - sweeping frequency - modulated continuous - wave sources are generated by two independent current - modulated distributed - feedback semiconductor lasers.

4. The common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals according to claim 1, characterized in that, Both Mach - Zehnder interferometer Ⅰ and Mach - Zehnder interferometer Ⅱ are composed of two 5:5 fiber - type couplers connected in series; the fiber - type coupler is used for optical signal coupling, outputs to the shared optical fiber delay line, and is also used for result output. The length of the shared optical fiber delay line is 10m.

5. The common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual-chirp signals according to claim 1, wherein The optical quadrature front - end includes a 90° optical phase shifter and two balanced detectors. After two optical signals pass through the optical quadrature front - end, an electrical beat - frequency signal with a 90° phase difference is output.

6. The common delay line and optical phase-locked loop link device for simultaneous phase-locking of dual chirp signals according to claim 2, characterized in that, The phase noise of the electrical signal output by the arbitrary function generator is -125 dBc / Hz@10 kHz within the frequency range of 0.1 kHz - 10 MHz; the electrical amplifier I and the electrical amplifier II are the same devices, providing an adjustable amplification / reduction multiple of 60 dB.

Images