RF Amplifiers Featured Articles

  1. SFDR Considerations In Multi-Octave Wideband Digital Receivers 4/14/2021

    Electronic warfare (EW) receivers must intercept and identify unknown enemy signals among a congested wideband spectrum of multiple interfering signals without the benefit of dynamic range and sensitivity improvement techniques employed in communications and radar receivers.

  2. GaN Breaks Barriers — RF Power Amplifiers Go Wide And High 4/12/2021

    The increasing demand for higher data rates in telecommunications and higher resolution in industrial systems is pushing the frequency of operation higher for their supporting electronics. Many systems operate over a wide frequency, so increased bandwidths are a common request for new designs. 

  3. Amplifier Selection Tips For EMC Applications 3/26/2021

    When choosing an amplifier for EMC testing, there are various factors to consider, including technology, class of operation, good linearity and low harmonic distortion, and more. 

  4. RF Field Probe Specifications And Design Characteristics 3/9/2021

    RF (Radio Frequency) field probes are an essential piece of equipment used for measuring the intensity of radiated RF fields. Although this instrument is crucial in implementing a radiation immunity test system, system specifiers often gloss over this essential element after spending a considerable amount of time and energy selecting amplifiers, antennas, and other equipment to generate the required RF field. Understanding the specification definitions, field probe design characteristics, and other varying features will, in turn, allow a confident and informed decision in choosing a suitable field probe.

  5. Linearity Of The JFET And MOSFET When In Saturation Over The Entire Cycle 11/18/2020

    Performing RF amplification in a way that is simultaneously linear and efficient has been a challenge in power amplifier (PA) design. Single transistor PAs can either be operated in a linear, but inefficient, current source mode of operation or as efficient, but nonlinear, switches. These techniques use two FETs, but this paper demonstrates that linear amplification can be achieved at high power with an efficiency greater than 60%, using a single FET.

  6. RF Amplifier Output Voltage, Current, Power, And Impedance Relationship 11/4/2020

    How much output voltage, current, and power can you expect from your amplifier? In rare cases, this can be answered by applying Ohm’s law, assuming that the net power or power delivered to the load is the rated power output of the amplifier. In most cases, practical issues such as VSWR and forward power concerns must be considered before applying Ohm’s law. This application note addresses this issue and discusses an approach to be used that applies actual test data when calculating output parameters.

  7. Application Guide To The A3 Series Of 10 kHz - 3 MHz Impedance Matching Amplifiers 11/4/2020

    Most RF amplifiers on the market have a nominal internal impedance of 50 Ω. However, many low to mid-frequency RF applications are characterized by impedances other than 50 Ω. It is not uncommon to encounter loads varying from 10 Ω to well over 200 Ω in this region. AR RF/Microwave Instrumentation has addressed this dilemma with the introduction of the A3 series of amplifiers that can incorporate a variable output impedance to better match those applications with load impedance other than 50 Ω.

  8. Utilizing Pulse Traveling Wave Tube Amplifiers 11/3/2020

    Pulse traveling wave tube amplifiers (TWTAs) offer a cost-effective source of high RF power for applications in which only a low to moderate RF duty cycle is required. A typical application is electromagnetic compatibility (EMC) RF pulse susceptibility testing. This application note discusses the unique specifications and characteristics applicable to pulse TWTAs.

  9. Importance Of Mismatch Tolerance For Amplifiers Used In Susceptibility Testing 11/3/2020

    RF amplifiers feature a nominal output impedance of 50 Ω and would ideally be used in applications where the load impedance is also 50 Ω. Unfortunately, broadband RF amplifiers used in “real life” applications that are characterized by load impedances other than 50 Ω. This application note will focus on the overlooked issue of mismatch in RF systems, the harmful effects of said mismatch, and how proper selection of the system amplifier can mitigate the ill effects of the mismatch.

  10. TWT Theory Of Operation 9/24/2020

    TWTs incorporate many basic components, including an electron gun, an RF circuit, an attenuator, and a collector. This white paper further discusses TWT characteristics and operational theory, including the effects of input/output conditions on TWTs, and cooling requirements.