Resonant transmission lines delivering precise RF voltages

Abstract

A system for transmitting a time-varying voltage signal from a first subsystem to a second subsystem and monitoring and controlling the time-varying voltage signal, the system comprising a transmission line having a first end and a second end, the transmission line extending from the first end at the first subsystem to the second end at the second subsystem. The transmission line is configured to be unterminated and has an electrical length that is approximately equal to a multiple of half the wavelength of the time-varying voltage signal. The system may also include: an adaptive control unit configured to connect the time-varying voltage signal to the first end and adjust a generator of the time-varying voltage signal based on sampling of the time-varying voltage signal at the first end; and at least one transformer at the second subsystem, the at least one transformer being electrically connected to the second end and configured to increase the amplitude of the time-varying voltage signal.

Description

[0001] Related Applications

[0002] This application is a continuation of U.S. Application No. 16 / 192,223 filed on November 15, 2018. The entire teachings of the above application are incorporated herein by reference. Technical Field

[0003] The present invention relates to resonant transmission lines for delivering precise RF voltages. Background Art

[0004] Quadrupole analyzers, such as those used in residual gas analyzers (RGA) and other mass spectrometers, require a precisely controlled two-phase RF power signal. The RF power signal amplitude is on the order of several hundred volts peak (Vpk), and its frequency is typically several MHz. The actual voltage amplitude and frequency may depend on the desired mass range and various characteristics of the quadrupole analyzer. A quadrupole analyzer application, for example, may utilize an RF power signal with an amplitude of 187.6 Vpk at 1.8432 MHz, but other voltages and frequencies may be selected to suit a particular analyzer and mass range.

[0005] A quadrupole analyzer typically consists of two major subsystems: a quadrupole subsystem (also referred to herein as the "vacuum system") that hosts the quadrupole device and associated hardware; and a signal generation, control, and analysis subsystem that hosts the RF signal generator, control and analysis components, and other supporting electronics.

[0006] The quadrupole subsystem may be exposed to ionizing radiation, which may degrade semiconductors and other components of the control / analysis subsystem. To protect these vulnerable components, the control / analysis subsystem may be remotely located relative to the quadrupole subsystem. In such a configuration, the quadrupole subsystem and the control / analysis subsystem may be connected by a cable or other communication medium and separated by a distance of typically tens of meters.

[0007] The RF signal generator is typically a fixed frequency, crystal-controlled component with an amplitude modulator configured to accurately control the RF signal amplitude through a control system. The control system includes an accurate rectifier that measures the RF signal voltage at the quadrupole system and uses the measurement as a feedback signal to the control system to maintain the RF signal amplitude at a desired value. The RF signal generator and associated control system are typically of a design known in the art.

[0008] It is common practice to collocate the rectifier with the quadrupole analyzer subsystem to accurately measure the amplitude of the RF signal being applied to the quadrupole. When the quadrupole is used in an ionizing radiation environment, the rectifier may be of thermionic diode type (e.g., vacuum tube) because semiconductor diodes degrade and / or fail in the presence of ionizing radiation. The rectifier output signal must be passed back to the control / analysis subsystem, which is inconvenient and risks introducing noise. There is also the problem of obsolescence of thermionic diodes and the complexity of the heater supply required to implement thermionic diodes. Summary of the invention

[0009] The described embodiments are directed to methods and systems that transmit RF signals over distances far greater than those traversed in prior art systems (e.g., 15 m) and remotely measure the RF signal voltage amplitude present at a quadrupole analyzer at a control / analysis subsystem. Extending the distance that the RF signal propagates keeps vulnerable components of the control / analysis subsystem safely away from the ionizing radiation environment. Remotely measuring the quadrupole RF signal voltage at the control / analysis subsystem helps position the rectifier at a safe distance from the ionizing radiation environment of the quadrupole analyzer, enabling the use of semiconductor rectifiers and thereby eliminating the need for thermionic rectifiers.

[0010] The described embodiments may include an open-ended transmission line extending between a quadrupole analyzer subsystem and a signal generation, control, and analysis subsystem that can resonate at the frequency of an RF signal. The resonant transmission line is configured such that the electrical length (i.e., the effective line length) is half the wavelength (λ / 2) of the operating frequency or an integer multiple of λ / 2. The example embodiments described herein may utilize a transmission line that is approximately 52 meters (λ / 2×1) or 104 meters (λ / 2×2) at an operating frequency of 1.8432 MHz, but other integer multiples of 52 meters may alternatively be used.

[0011] The input and output voltages of a resonant transmission line are approximately the same when driven at its resonant frequency (i.e., the frequency at which the electrical length of the transmission line is n×(λ / 2), where n is an integer). Thus, using a half-wavelength resonant transmission line, the RF signal voltage amplitude present at the quadrupole analyzer subsystem can be accurately measured remotely at the signal generation, control, and analysis subsystems using semiconductor diodes as rectifiers. At resonance, the transmission line impedance is purely resistive, which avoids the inefficiencies associated with complex impedances and eliminates the need for matching terminations at the receiving end of the transmission line.

[0012] The described embodiment may also include a pair of step-up transformers at the quadrupole analyzer end of the half-wavelength transmission line. The step-up transformer facilitates the use of a lower voltage on the transmission line than required by the quadrupole itself. In the example embodiment, the turn ratio of the step-up transformer is 1:5, but alternative embodiments may use other turn ratios. For this example embodiment, an RF signal with an amplitude of 187 Vpk at the quadrupole corresponds to an RF signal with an amplitude of approximately 37.4 Vpk on the transmission line. The lower voltage on the transmission line helps reduce dissipative losses compared to a transmission line that provides an RF signal to the quadrupole without a transformer.

[0013] A system is provided for transmitting a time-varying voltage signal from a first subsystem to a second subsystem and for monitoring and adaptively controlling the amplitude of the time-varying voltage signal. The system includes a transmission line having a first end and a second end, the transmission line extending from the first end at the first subsystem to the second end at the second subsystem. The transmission line is configured so that the physical length corresponds to the electrical length of the transmission line, the electrical length of the transmission line is approximately equal to a positive integer multiple of half the wavelength of the time-varying voltage signal, and the transmission line is configured to be resonant. An adaptive control facility at the first subsystem is configured to (i) electrically connect the time-varying voltage signal to the first end, and (ii) based on sampling of the time-varying signal at the first end, adjust a generator of the time-varying voltage signal to maintain the amplitude of the time-varying voltage signal at a desired level. At least one transformer at the second subsystem is electrically connected to the second end of the transmission line and is configured to increase the amplitude of the time-varying voltage signal.

[0014] The first subsystem may include signal generation, control and analysis electronics, and the second subsystem may include a quadrupole analyzer.The time-varying voltage signal may be a radio frequency voltage signal configured to be applied to a quadrupole component of the quadrupole analyzer via the at least one transformer.

[0015] The adaptive control facility may include a rectifier configured to sample a time-varying voltage signal at a first end of the transmission line and generate a feedback signal based on the sampling. The adaptive control facility may be configured to adjust a generator of the time-varying voltage signal based on the sampling of the time-varying voltage signal at the first end to maintain the amplitude of the time-varying voltage signal at a desired level. The rectifier may be a semiconductor diode. The compensation diode may be electrically coupled to the rectifier. The compensation diode may be configured such that a change in the conduction voltage of the compensation diode relative to temperature mitigates a change in the conduction voltage of the rectifier relative to temperature.

[0016] At least one transmission line length selected from a variety of line lengths is added to the transmission line. The at least one transmission line length is configured to provide a coarse adjustment of the electrical length of the transmission line by adjusting the physical length of the transmission line if the transmission line is not within an adjustment range for fine adjustment. Fine adjustment may be by an adjustable capacitor coupled in parallel with a first end of the transmission line, the adjustable capacitor being configured to provide compensation to resonate the transmission line.

[0017] A tunable tank circuit may be configured to receive an excitation signal from a signal generator and resonate at a frequency of the excitation signal to generate a time-varying voltage signal.

[0018] The at least one transformer may include two transformers electrically coupled to the time-varying voltage signal to generate two phases of the time-varying voltage signal. Alternatively, the at least one transformer may include a single transformer having a primary winding and two secondary windings configured to generate two phases of the time-varying voltage signal applied to the primary winding.

[0019] The transmission line may be a component of a cable assembly that includes one or more communication paths for conveying one or more of information, control signals, and power between the first subsystem and the second subsystem. The first subsystem may be at least half a wavelength from the second subsystem. For example, the first subsystem may be at least 30 meters from the second subsystem, or at least 50 meters from the second subsystem.

[0020] In a method for transmitting a time-varying voltage signal from a first subsystem to a second subsystem and monitoring and adaptively controlling the amplitude of the time-varying voltage signal, the time-varying voltage signal is electrically connected to a first end of a transmission line extending from the first end at the first subsystem to a second end at the second subsystem. The physical length of the transmission line is configured to correspond to an electrical length that is approximately equal to a positive integer multiple of half the wavelength of the time-varying voltage signal. At an adaptive control facility at the first subsystem, a generator of the time-varying voltage signal is adjusted based on sampling of the time-varying voltage signal at the first end to maintain the amplitude of the time-varying voltage signal at a desired level. The amplitude of the time-varying voltage signal is increased using at least one transformer at the second subsystem, the at least one transformer being electrically connected to the second end. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The foregoing will become apparent from the following more particular description of example embodiments as illustrated in the accompanying drawings, in which like reference numerals refer to the same parts throughout the different views. The drawings are not necessarily drawn to scale, emphasis instead being placed upon illustrating the embodiments.

[0022] Figure 1A An example of a mass spectrometer system according to the present invention is depicted.

[0023] Figure 1B Illustrated Figure 1A A more detailed view of an example mass spectrometer is shown.

[0024] Figure 2 A more detailed view of an example embodiment of a system for transmitting a time-varying voltage signal according to the present invention is shown.

[0025] Figure 3 An exemplary method of transmitting a time-varying voltage signal from a first subsystem to a second subsystem and monitoring and adaptively controlling the amplitude of the time-varying voltage signal according to the present invention is illustrated. DETAILED DESCRIPTION

[0026] A description of example implementations follows.

[0027] The teachings of all patents, published applications, and references cited herein are incorporated by reference in their entirety.

[0028] The described embodiments are directed to transmitting an RF signal over a distance far greater than that traversed in prior art systems, and remotely measuring the RF signal voltage amplitude present at a quadrupole analyzer at a control / analysis subsystem. Typically, the described embodiments utilize a resonant transmission line configured such that its electrical length is one-half the wavelength of the RF signal to transmit the RF signal to the quadrupole analyzer. A characteristic of a resonant transmission line is that it exhibits the same RF voltage amplitude at both ends of the transmission line.

[0029] Figure 1A An example of a mass spectrometer system 100 that can employ the described embodiments is depicted. System 100 can include a quadrupole subsystem 102, a signal generation, control and analysis subsystem 104, and a cable assembly 106 connecting subsystems 102, 104. Quadrupole subsystem 102 can reside in an adverse environment (e.g., a "hot" radiation area), while signal generation, control and analysis subsystem 104 can reside in a normal safe area away from the adverse environment. The distance away from the adverse environment that is considered necessary for a safe environment depends on the nature of the adverse environment. Although less adverse environments may require a distance of 5 to 15 meters (and therefore require a length of 5 to 15 meters for cable 106), more severe environments (for example, nuclear physics applications such as particle accelerators and high-density neutron generators) may require a separation distance of 50 meters or more.

[0030] Figure 1B Illustrated Figure 1AA more detailed view of an example mass spectrometer 100 is shown. Components of the described embodiment of a system for transmitting a time-varying voltage signal 108 are depicted within the dashed box. These components will be described in more detail below, following a description of the overall system within which the described embodiment resides.

[0031] Quadrupole system 102 may include a vacuum system 110 including an ion source and lens assembly 112, a quadrupole analyzer 114, and a Faraday plate and electron multiplier assembly 116, and a pair of step-up transformers 118. Quadrupole system 110 may operate in an ionizing radiation environment, i.e., a "hot" radiation region 120.

[0032] The signal generation, control, and analysis subsystem 104 is an adaptive control facility that may include a power supply and electronic control system component 122 , and a transmission line driver and rectifier component 124 .

[0033] The cable assembly 106 (which preferably includes the illustrated cables and signal lines in a single cable sheath) can include a main cable 126 that delivers power from the power supply and electronic control system assembly 122 to the ion source and lens assembly 112. The cable assembly 106 can also include a return signal cable 128 that transmits the detection signal from the Faraday plate and electron multiplier assembly 116 to the power supply and electronic control assembly 122. The cable assembly 106 can also include a coaxial transmission line 130, and one or more binary-weighted line lengths 132.

[0034] Figure 2 A more detailed view of an example implementation of a system 108 for transmitting a time-varying voltage signal according to the present invention is shown. The example implementation includes a tuned oscillator circuit 202, a rectifier circuit 204, a temperature compensation circuit 206, an effective line length adjustment component 208, a half-wavelength transmission line 130, and a transformer 212.

[0035] The tuning circuit 202 receives an RF signal 214 from a crystal-controlled RF generator within the power supply and electronic control assembly 122. The values ​​of components L1, L2, and C1 are selected to form an oscillating circuit that resonates at the frequency of the RF signal 214, thereby reducing harmonics from the modulator and maximizing the amplitude at the resonant frequency. Variable capacitor C2 can be used to adjust the resonant frequency to match the frequency of the RF signal 214. The tuning circuit 202 drives the RF signal to the transmission line 130 through capacitor C3, which provides DC isolation, and through a driving impedance R2. The driving impedance R2 provides buffering during the system power-up transition when the resonant components may not yet be in tune. During such a transition, unpredictable reflections may flash along the transmission path, which may damage the component components. The driving impedance R2 can mitigate such reflections. In steady state, when the resonant components are in tune, R2 presents a matching impedance to the transmission line 130.

[0036] The rectifier circuit 204 employs a semiconductor diode D1 to rectify a representative sample of the RF voltage signal at the input of the transmission line 130. The rectified sample passes through R4 to generate a feedback current, which is delivered to the power supply and electronic control assembly 122. The feedback current is used by the control system in the power supply and electronic device control assembly 122 to adaptively maintain the RF signal amplitude at a desired value.

[0037] Diode D1 is affected by a temperature coefficient such that as the temperature of diode D1 increases, the forward conduction voltage of D1 decreases by about a few millivolts per degree Celsius. The RF signal voltage needs to be precisely controlled for use with a quadrupole analyzer. Since the RF signal voltage has a relatively wide dynamic range, errors caused by the temperature coefficient that exceed the system operating temperature range may adversely affect operation at the lower end of the dynamic range.

[0038] Temperature compensation circuit 206 operates to counteract the effects of the temperature coefficient of D1. Temperature compensation circuit 206 includes diode D2, which is electrically coupled opposite diode D1 and positioned sufficiently close to diode D1 so that D1 and D2 experience approximately the same ambient temperature. Diode D2 is biased by a -15V supply through R18. Diode D2 is selected to have approximately the same temperature coefficient as diode D1, so that as the common ambient temperature changes, the change in the bias point of D2 causes the bias point of D1 to be moved by an equal amount.

[0039] The transmission line 130 receives an RF signal from the tuning circuit 202 through the capacitor C3 and the driving impedance R2. The transmission line 130 is configured to have a physical length that is approximately an electrical length (also referred to herein as an effective length) that is half the wavelength (λ) of the RF signal. For this electrical length or an integer multiple of this length, the transmission line 130 resonates at the frequency of the RF signal. The wavelength of the signal in the transmission line is given by the following formula:

[0040]

[0041] Where f is the frequency of the RF signal and v is the velocity factor of the propagation medium. In an example embodiment, the transmission line 130 is an RG58 coaxial cable, which has a specified velocity factor v of 0.66. At an RF signal frequency of 1.8432 MHz and using the specified velocity factor, the λ / 2 electrical length of the RG58 cable should be 53.71 m. However, in practice, resonance occurs at a transmission line length of 51.79 m, which means that the actual velocity factor is approximately 0.6364.

[0042] The transmission line 130 may be adjusted or "tuned" to provide the proper electrical length to resonate at the frequency of the RF signal by one or both of two adjustment resources. (This is only necessary if the transmission line is not within the fine adjustment range of capacitor C6 mentioned below.) Coarse adjustment may be accomplished by inserting one or more line lengths 132, such as Figure 1B These line lengths 132 can be used to adjust the electrical length of the transmission line by simply changing the physical length of the transmission line 132. Figure 1B The exemplary embodiment shown depicts binary-weighted line lengths 132 of 2 m, 1 m, and 0.5 m, but other values ​​of binary or otherwise weighted line lengths 132 may be used in addition to or in place of the values ​​listed.

[0043] Fine tuning can be accomplished by manipulating variable capacitor C6 on the drive side of transmission line 130. Variable capacitor C6 operates as a reactive load on transmission line 130, and the value of C6 can be adjusted so that the combination of variable capacitor C6 and transmission line resonates at the frequency of the RF signal.

[0044] An example process for tuning the transmission line 130 may be to apply an RF signal to the transmission line 130 and observe the RF signal voltage at the transmission line input. Transmission line length 132 may be selectively added to the transmission line 130 until a maximum value of the RF signal voltage is observed. Then, the variable capacitor C6 may be adjusted until a maximum value of the RF signal voltage is observed. Alternatively, other tuning processes known in the art may be used.

[0045] Transformer 212 receives the RF signal propagated by transmission line 130 and increases the RF signal voltage for use by quadrupole analyzer 114. The transformers receive RF signals of opposite polarity so that the transformers generate stepped-up RF signal voltages of different phases, with the output of one transformer shifted 180 degrees relative to the output of the other transformer.

[0046] In an example embodiment, the transformer 212 may include two separated but closely coupled transformers, each having a turns ratio of 1:5, so that the RF signal voltage at the output of the transformer is five times the RF signal voltage at the input of the transformer. However, it should be understood that other turns ratios may be used alternatively. The transformer is also adjustable to tune the four-pole capacitance. In another example embodiment, the transformer 212 may include a single transformer having a primary winding and two secondary windings. Using a step-up transformer, a reduced voltage signal can be transmitted on a transmission line to keep the losses (which are proportional to the square of the RF signal voltage) to an acceptable level. In an embodiment, one or both of the transformers may have adjustable taps to facilitate adjusting the secondary winding output voltage relative to the primary winding input voltage.

[0047] Figure 3 An example method 300 of transmitting a time-varying voltage signal from a first subsystem to a second subsystem and monitoring and adaptively controlling the amplitude of the time-varying voltage signal according to the present invention is illustrated. The method may include the steps of electrically coupling 302 the time-varying voltage signal to a first end of a transmission line extending from the first end at the first subsystem to a second end at the second subsystem. The method may also include the steps of configuring 304 the transmission line so that (i) the transmission line has an electrical length substantially equal to a positive integer multiple of half a wavelength (λ / 2) of the time-varying voltage signal; and (ii) the transmission line is unterminated. The method may also include the steps of adjusting 306 a generator of the time-varying voltage signal based on sampling of the time-varying voltage signal at the first end using an adaptive control facility at the first subsystem. The method may also include the steps of increasing 308 the amplitude of the time-varying voltage signal using at least one transformer at the second subsystem, the at least one transformer being electrically coupled to the second end.

[0048] While several example embodiments have been particularly shown and described, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the embodiments as encompassed by the appended claims.

Claims

1. A system for transmitting a time-varying voltage signal from a first subsystem to a second subsystem and monitoring and adaptively controlling the amplitude of the time-varying voltage signal, the system comprising: a transmission line having a first end and a second end, the transmission line extending from the first end at the first subsystem to the second end at the second subsystem, the transmission line being configured to have a physical length corresponding to an electrical length of the transmission line, the electrical length of the transmission line being substantially equal to a positive integer multiple of half a wavelength of the time-varying voltage signal, the transmission line being configured to be resonant; an adaptive control facility at the first subsystem, the adaptive control facility being configured to (i) electrically couple the time-varying voltage signal to the first terminal, and (ii) adjust a generator of the time-varying voltage signal based on sampling of the time-varying voltage signal at the first terminal to maintain a magnitude of the time-varying voltage signal at a desired level; as well as At least one transformer at the second subsystem is electrically coupled to the second end and is configured to increase the amplitude of the time-varying voltage signal.

2. The system according to claim 1, comprising: The first subsystem includes signal generation, control and analysis electronics, and the second subsystem includes a quadrupole analyzer, and wherein the time-varying voltage signal is a radio frequency voltage signal configured to be applied to a quadrupole component of the quadrupole analyzer through the at least one transformer.

3. The system according to claim 1, wherein: The adaptive control facility includes a rectifier configured to sample the time-varying voltage signal at the first end of the transmission line and to generate a feedback signal based on the sampling.

4. The system according to claim 3, wherein: The rectifier is a semiconductor diode.

5. The system of claim 4, further comprising a compensation diode electrically coupled to the rectifier, the compensation diode being configured such that a change in conduction voltage of the compensation diode with respect to temperature mitigates a change in conduction voltage of the rectifier with respect to temperature.

6. The system of claim 1 , further comprising at least one transmission line length selected from a variety of line lengths, the at least one transmission line length being added to the transmission line, the at least one transmission line length being configured to provide a coarse adjustment of the electrical length of the transmission line by adjusting the physical length of the transmission line.

7. The system of claim 1, further comprising an adjustable capacitor coupled in parallel with the first end of the transmission line, the adjustable capacitor configured to provide compensation to place the transmission line in resonance. 8 . The system of claim 1 , further comprising a tunable oscillator circuit configured to receive an excitation signal from a signal generator and resonate at a frequency of the excitation signal to generate the time-varying voltage signal.

9. The system according to claim 1, wherein: The at least one transformer includes two transformers electrically coupled to the time-varying voltage signal to generate two phases of the time-varying voltage signal.

10. The system according to claim 1, wherein: The at least one transformer includes a single transformer having a primary winding and two secondary windings configured to generate two phases of the time-varying voltage signal applied to the primary winding.

11. The system according to claim 1, wherein: The transmission line is a component of a cable assembly that includes one or more communication pathways for conveying one or more of information, control signals, and power between the first subsystem and the second subsystem.

12. The system according to claim 11, wherein: The first subsystem is located at least half a wavelength away from the second subsystem.

13. The system according to claim 11, wherein: The first subsystem is located at least 30 meters from the second subsystem.

14. A method for transmitting a time-varying voltage signal from a first subsystem to a second subsystem and monitoring and adaptively controlling the amplitude of the time-varying voltage signal, the method comprising: electrically coupling the time-varying voltage signal to a first end of a transmission line extending from the first end at the first subsystem to a second end at the second subsystem, configuring the physical length of the transmission line to correspond to an electrical length substantially equal to a positive integer multiple of half the wavelength of the time-varying voltage signal; adjusting, at an adaptive control facility at the first subsystem, a generator of the time-varying voltage signal based on sampling of the time-varying voltage signal at the first terminal to maintain the amplitude of the time-varying voltage signal at a desired level; as well as The amplitude of the time-varying voltage signal is increased using at least one transformer at the second subsystem, the at least one transformer being electrically coupled to the second end.

15. The method according to claim 14, further comprising: The time-varying voltage signal at the first end of the transmission line is sampled and a feedback signal is generated based on the samples.

16. The method according to claim 14, further comprising: At least one binary-weighted transmission line length selected from a variety of transmission line lengths is added to the transmission line to provide a coarse adjustment of the electrical length of the transmission line by adjusting the physical length of the transmission line.

17. The method according to claim 14, further comprising: An adjustable capacitor coupled in parallel with the first end of the unterminated transmission line is adjusted to provide compensation to place the transmission line in resonance.

18. A system for transmitting a time-varying voltage signal from a first signal generation, control and analysis subsystem to a second quadrupole analyzer subsystem and monitoring and adaptively controlling the amplitude of the time-varying voltage signal, the system comprising: The signal generation, control and analysis first subsystem; The quadrupole analyzer second subsystem has a quadrupole analyzer, the time-varying voltage signal is a radio frequency voltage signal, and the radio frequency voltage signal is configured to be applied to a quadrupole component of the quadrupole analyzer through at least one transformer; a transmission line having a first end and a second end, the transmission line extending from the first end at the first subsystem to the second end at the second subsystem of the quadrupole analyzer, the transmission line being configured to have an electrical length substantially equal to a positive integer multiple of half a wavelength of the time-varying voltage signal; a rectifier circuit configured to sample the time-varying voltage signal coupled to the first terminal to generate a feedback signal and to transmit the feedback signal in an adaptive control facility configured to adjust a generator of the time-varying voltage signal based on the sampling of the time-varying voltage signal at the first terminal to maintain the amplitude of the time-varying voltage signal at a desired level; and At least one transformer at the second subsystem of the quadrupole analyzer is electrically coupled to the second end and is configured to increase the amplitude of the time-varying voltage signal.

19. The system of claim 18, further comprising a temperature compensation circuit electrically coupled to the rectifier, the temperature compensation circuit configured to mitigate changes in conduction voltage of the rectifier relative to temperature based on changes in conduction voltage of a compensation diode of the system relative to temperature.

20. The system of claim 18, further comprising at least one transmission line length selected from a variety of line lengths, the at least one transmission line length being added to the transmission line, the at least one transmission line length being configured to provide a coarse adjustment of the electrical length of the transmission line by adjusting the physical length of the transmission line.

21. The system of claim 18, further comprising an adjustable capacitor coupled in parallel with the first end of the transmission line, the adjustable capacitor configured to provide compensation to place the transmission line in resonance.

22. A method for transmitting a time-varying voltage signal from a signal generation, control and analysis subsystem to a second subsystem of a quadrupole analyzer and monitoring and adaptively controlling the amplitude of the time-varying voltage signal, the method comprising: electrically coupling the time-varying voltage signal to a first end of a transmission line extending from the first end at the signal generation, control, and analysis subsystem to a second end at the quadrupole analyzer; configuring the physical length of the transmission line to correspond to an electrical length substantially equal to a positive integer multiple of half the wavelength of the time-varying voltage signal; sampling the time-varying voltage signal coupled to the first terminal with a rectifier circuit to generate a feedback signal, and transmitting the feedback signal to an adaptive control facility, the adaptive control facility being configured to adjust a generator of the time-varying voltage signal based on the sampling of the time-varying voltage signal at the first terminal to maintain the amplitude of the time-varying voltage signal at a desired level; as well as The amplitude of the time-varying voltage signal is increased using at least one transformer at the second subsystem of the quadrupole analyzer, the at least one transformer being electrically coupled to the second end.

23. The method according to claim 22, further comprising: Variations in conduction voltage of the rectifier with respect to temperature are mitigated based on variations in conduction voltage with respect to temperature of a compensation diode of the signal generation, control, and analysis subsystem.

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