A Waveguide rotary joint is used to connect two different types of RF waveguides used in an application. In the rotating part the electrical continuity is achieved by using certain types of chokes eliminating the metal contacts.

Waveguide rotary joint has ports in U-style, L-style, or both the ports in I-style, vis-à-vis its rotational axis. Rotary joints are available for all frequency bands.

Waveguides rotary joints, also known as RF rotary joints, are used to transmit microwave energy from fixed lines to the rotating ones without degradation in their performance.

Waveguide rotary joint differs in terms of its fabrication, material used, cross-sections, and most importantly, its physical dimensions.

Most rotating joints have differently shaped cross-sections made of aluminum, brass, copper, and silver. However, its components are made of stainless steel, specialty steels, or jacketed bi-metallic alloys.

Flexible or twistable single, double, or quad ridged waveguide rotary joint components with as many apertures are also available in the trade. Waveguide dimensional parameters are very important to achieve calibrated output performance.

Performance features like frequency range, EIA size, VSWR, insertion loss and isolation are integral specifications that decide its presence and appropriateness in a circuitry.

Although waveguide rotary joints are manufactured as per U. S. military specification, it may be also customized as per required industrial or commercial specifications. A full range can be seen on the Raditek website.

OXCO is actually a normal quartz crystal oscillator that is housed in a mini thermostatic oven in order to maintain an constant (required) temperature at all times and conditions.

Changes in the temperature can cause a drift in the center frequency and drastically jeopardize the calibrated output parameters. And therefore, the use of oven-controlled crystal oscillators becomes eminent.

Aside from the oven, quartz crystal temperatures are also managed by providing it with various forms of trimming known as “Cuts,” which also aids in preserving the pulse’s stability.

However, it is necessary to carry out checks and recalibrate crystal and heat element aging to ensure accurate performance at all times.

OCXO is the top-performing quartz with remarkable frequency stability. As a result, they are used in the precision applications and systems like cell towers, commercial radio transmitters, and military communication equipment.

Though an OXCO is bigger, expensive, and consumes a greater power than its regular equivalents, it compensates for these disadvantages by providing super frequency stability over a long period of time that the conventional oscillators cannot offer.

There are two types of Oven-ized crystal oscillators available on the market:

These are used basis the application designs and circuitry needs. See Raditek website.

Waveguide rotary joint is used to connect two different types of RF waveguides in a communication system. With the use of a waveguide rotary joint, a free rotational movement can be achieved without degrading the performance of microwave RF signals.

A waveguide rotary joint component is an electro-mechanical component used to transmit microwave signals-radio bands or a pulse from other spectrum-from a stationary line to a rotating line or vice versa.

The needed electrical continuity in a waveguide rotary joint is achieved by using λ/4-chokes which eliminates metal contacts that are susceptible to metal fatigue and wear and tear.

A waveguide rotary joint can have both the waveguide ports a right angle to the rotational axis, or have a “U-style”, “L-style” or an “I-style” configuration depending upon the modules which are available across the frequency bands.

Most waveguide rotary joint use rectangular, circular, or elliptical cross-section made of aluminum, brass, bronze, copper, silver, stainless steel and metallic alloys.

Waveguide rotary joint is extensively used in airport surveillance radars, guided missile technology, and other radar applications.

Its rugged make, minimum phase WOW, stable phase linearity make a waveguide rotary joint a perfect fit for high power applications. These can also be which can also be custom-made for a specific design/application.

The quartz crystal in an electronic oscillator needs to be maintained at a constant operating temperature to prevent changes in its frequency due to variations in the ambient temperature.

Therefore, in order to maintain the crystal oscillator at a required temperature, it is housed in an oven with the thermostat devise that indicates the existence of the calibrated oven temperature. Such an improvised devise is called OCXO-Oven controlled crystal oscillator.

Normal operating temperature of a standard commercial OCXO is 75 °C but would vary from 30 – 80 °C depending upon the set-up and that of its industrial version is specified to -40 – +85 °C

Thus, such a design of an OCXO prevents temperature drifts and provides the highest stability that a crystal oscillator can provide. Further, frequency stability is also fine-tuned by the types of cuts on the quartz crystal-AT Cut and SC Cut.

Therefore it is quite obvious that OCXO is predominantly used in applications where the frequency control is a crucial factor like radio transmitters, cellular base stations, defense communication devices, and precision frequency measurement equipment.

OCXO is bulkier in size, expensive and power-consuming. However, the frequency and temperature stability provided by OCXOs are much better than what the TXCOs provide.

Routine service checks are recommended to assess the health of performing elements.

Microwave amplifiers are vital solid-state devices in the frequency range of 1to 100GHz to enhance the power, amplitude, or the oscillation span of input signals without providing additional distortion to its waveform, spectral composition and signal-to-noise ratio.

In other words, microwave amplifiers provide gain, stability, power, and linearity to the microwave signals received by it in a system.

Microwave amplifiers are used in all sorts of common electronic systems as also in ultra-tech electronic systems like electromagnetic compatibility systems (EMC), electromagnetic interference (EMI), defense systems, medical aid, and diagnostic systems, laboratory and field testing devices.

Microwave amplifiers are classified in many different ways. However, there are four broad categories based on the role it plays in generic super-heterodyne receiver.

Low noise amplifiers (LNA): Simple microwave amplifiers-takes low level signals from the transmission medium and amplifies it with minimal additional noise.

Power Amplifier (PA): Amplifies high level signals received and enhance it further to transmit it over lossy medium.

Linear signal amplifier (LSA): Generic amplifiers also called gain blocks. Provides signal gain with a system.

Driver amplifier (DA): Suited for single frequency operations as in synthesizers or amplifiers for local oscillator (LO) driving a mixer.

Microwave amplifier generates a lot of heat; hence need to ensure that it has a built-in cooling system, integral to its performance.

Rubidium Oscillators are a type of atomic clock with the most accurate time standards-not as precise as Cesium, though-which is used as a time distribution service to superintend telecommunication infrastructure, Television broadcast, aerospace, defense sector, and global navigation satellite systems.

Normal oscillator circuits are prone to energy loss resulting in weak amplitude.

Hence, in order to maintain consistency of accurate oscillation at constant amplitude, rubidium “physics circuitry” is used in OCXOs. Such oscillators are called rubidium oscillators.

Rubidium oscillators are basically improvised OCXOs wherein the accuracy of rubidium oscillation further secures oven-controlled crystal oscillator’s frequency output in terms of timing accuracy, and its amplitude.

It is known that the frequency pulse of an OXCO tends to change over time resulting in inaccurate periodicity of its pulse, on account of which, it may be faster or slower.

Such changes/discrepancies are detected by the rubidium section which then swaps it with the correct frequency pulse at the output stage.

In other words, rubidium oscillators ensure the most accurate frequency at the output level and thereby making it the most dependable oscillator for all electronic applications and systems.

In technical terms, rubidium oscillators harness the OCXO frequency output to rubidium hyperfine transition/cycle of 6 834 682 610.904 Hz.

More than twenty types of rubidium oscillators are used in various applications.

The function of any amplifier, including the SSPA (solid-state power amplifier) is to increase or add to the power charge on its input signals. Solid-state amplifiers can amplify signals in the range 30KHz to 300GHz.

SSPA is commonly used in cellular networking and broadcasting systems. Its shape and size can be varied as needed by the circuit topography, especially in satellite communication applications.

SSPA is the most integral device for satellite and broadcasting applications. It performs the crucial function; that of amplifying weak radio frequencies signals-as received by the antennas- to the required amplification level.

In any amplifier, it is the transistors that carries out the bulk of the amplification job. Gallium Arsenide (GaAs) based transistors for SSPA were popular earlier, on account of its quick-replacement feature.

In recent times, however, the transistor based on gallium nitrate (GaN) is primarily used in SSPAs, as it provides improved efficiency without signal loss as compared to GaAs based SSPAs.

Earlier, for L, S, and C band satellite communications, GaN transistor-based SSPA was used. But now, for high frequencies like X, Ku, and Ka frequency bands, advanced GaN-based SSPAs are being used.

In addition, millimeter and microwave applications like radar and electronic warfare also use SSPAs with GaAs and/or GaN transistors.

Further, GaN-based SSPAs can withstand high operating temperatures without degrading any of the output parametric. GaN-based SSPA is said to be the most reliable amplifier on account of its lower maintenance down-time and savings on OPEX cost.

Raditek Inc provides SSPA covering the range 30KHz to 90GHz.  See the Raditek Inc website.

A Band pass filter (BPF) is used to block the unnecessary frequencies and allow only the required frequencies to pass further into a system, appliance, or application. An integrated system decides the requisite resonant frequencies and the unnecessary frequencies get removed with digital or a band pass filter.

In essence, the band pass allows only those signals that are required by the transmission parametric Signals outside of the specified band is attenuated but not completely rejected, which is termed as “roll-off”.

The pass filters help to keep such roll-offs to be as narrow as possible so that it performs as close to the designed parameters. This function prevents the wireless stations from a mix-up of frequencies resulting in a detrimental outcome.

Filters are divided into four groups, defined by their relative cut-off frequency values-High-pass, Low-pass, band-pass and band-stop filters.

Among the above groups, a band pass filter has two categories – Active and passive band pass filters. Active BPF uses active components like transistor and Op-Amp for filtering electronic signals and the passive BPF uses passive components like resistors, inductors, and capacitors to generate a frequency band.

Active BPF is highly effective in dealing with the very low frequencies-close to 0 Hz and yields a very high gain, however, is unsuitable for very high-frequency applications. Passive BPF is of utmost usefulness for the 100Hz to 300MHz frequency range.

Band pass filter is used in applications like power supplies, audio electronics, radio communications, and lighting equipment.

All types of filters are available from Raditek Inc. examples can be seen on the Raditek website.

Microwave amplifiers are devices that boost the voltage or power of the radio frequency that is fed into it from various sources like the antenna and or from other systems.

Microwave amplifiers are a solid-state RF device that provides gain, stability, power, linearity and noise reduction to the input signal and amplifies it as per the set parameters.

Solid-state amplifier systems use transistors that either have Gallium Arsenide (GaAs) or Gallium Nitrate (GaN), which is responsible for the actual amplification of the input signal. GaAs transistor has the best linearity and the GaN transistor has the best efficiency.

A microwave amplifier is a very crucial, critical, and integral device that handles a frequency range from 1 to 100GHz.

And therefore it extensively used in electromagnetic compatibility systems (EMC), Defense systems, medical and diagnostic systems, lab and field testing appliances and point to point microwave link systems.

Microwave amplifiers are fundamental devices in modern-day electronics and are a part of all electronic devices that deal have to deal with the electronic audio/video communications.

There are various types of microwave amplifiers and that includes 1) The Gyrotron, 2) The Klystron and 3) the Amplitron-also is known as Crossed-Field Amplifier (CFA) or Platinotron.

Microwave amplifiers are prone to heating up and hence amplifiers made by reputed companies have a robust built-in state of art cooling systems like the convection cooling heat sink or forced air cooling apparatus and for ultra-high power amplifiers, water cooling systems are also used.

See the Raditek website.

Coupler coaxial is a very basic microwave device used in almost all the microwave applications and systems. It is widely used in the telecommunication sector, test gadgets, instruments and in commercial applications like medium-power transmitters, aerospace industry and military communication systems.

While the splitter degrades signals (3dB), coupler coaxial, on the other hand dissipates it to the extent of only 0.5dB.

There are different types of coaxial couplers BNC, MCX, N-type, F-type, SMT, UHF, TNC-SMC, and a few other N-types which are high-performance couplers used in multiple applications mentioned above.

Electronic engineers across the global are replacing the bulky cable assemblies with the simple board to board coupler coaxial that can handle the power load of 100w which reduces the weight and space utilized.

These days, micro coaxial couplers are available for various applications which are suitable for 10GHz and are 30% smaller in size to their predecessors.

Then there are directional coaxial couplers that are suitable to cover frequency bands from 0.25-40.0 GHz in multi-octave and octave band configurations.

In addition to the above types of coaxial couplers there are coaxial waveguide couplers, Ka and Ku Band coaxial couplers.

In certain applications, it becomes necessary to connect the transmission lines coming from the coupler coaxial to strip transmission lines. For this purpose, advanced coaxial couplers and connectors are now available which compensate for the impedance mismatch and phase shift.

Such an adaptable convertibility allows for interchangeability of couplers and connectors for further tasks without disconnecting the lines.

See the Raditek website.