Picture and voice quality in television and the download speed of the internet highly depends on the Coaxial Coupler. So, it becomes necessary to buy a well-performing coupler to get high definition quality picture and sound.

The most important thing to look for is to ensure that the connector is compatible with Dish Network, Wi-Fi radios, off-air antenna systems, and wireless LAN Devices as well as with Cable Internet Svc (including Cox, Charter, and Comcast, etc.). It should have been manufactured from superior quality, weather resistant material possessing extremely low signal attenuation.

It should be easy to use so that even a novice can install without requiring to cut, splice or tools. You can find one coupler for both indoor and outdoor use. You must also know which coax cable you have to connect like RG58, RG59, FG6, and RG11 coaxial cable. These cables might be with wall plates for outdoor and for indoor use.

You must also check the signal loss in the coupler as the signal loss is inevitable. Signal consistently degrade while passing through be it any device. What you can do is it to ensure the least signal loss. There is high-quality Coaxial Coupler available ensuring least signal loss and excellent quality audio, video.

You must look for all these qualities before buying a coupler online. Do ask the manufacturer about the specifications and warranty on the product as the products manufactured with the high-quality material are durable giving consistent throughout their life.

A circulator is a three port device. It is essentially a passive device, but can exhibit some characteristics that make it almost behave as if it were active. An isolator is a two port device having an input and an output, it is simply a circulator whose third port has been terminated.

Circulators and Isolators provide unique transmission paths, allowing RF energy to pass in one direction with little (insertion) loss, but with high loss (isolation) in the other direction.

Isolators and circulators can exist as Stripline, Coaxial, Microstrip, or Waveguide type, and can be rated for powers from milliwatts to Megawatts. Raditek can provide superb stripline isolators to 18GHz, Microstrip ones to 60 GHz. Coaxial to 50Ghz and Waveguide to 110GHz.

A typical use of a circulator would be as a duplexer, connecting a transmitter to Port 1, antenna to port 2 and receiver to port 3. This provides simultaneous transmission and reception of signals.

A very common use for isolators is at the output of a power amplifier. Forward power is passed with a minimal insertion loss. Reverse power resulting from disconnect at the output (removing the connection to antenna), will (with no isolator installed) flow back to the output FET/LDMOS etc. and likely damage or destroy it/them. With the isolator installed, any reflected power will flow into the isolator’s load and be safely dissipated as heat (as long as the load is rated to handle the power, and is properly heat sunk, so that the load temperature stays <100C).

Typical parameters could be 0.25dB insertion loss, 22dB isolation and VSWR on the ports of 1.2:1 over a 5% percentage bandwidth.

The Raditek isolators and circulators are believed to have the best performance in the marketplace, within constraints and compromises of physical size, power, and RF performance.

Block Upconverter (BUC) converts a band of frequencies. It is used to convert the frequency from lower to higher. BUC is used in the transmission of satellite signals. BUCs are used to convert L band to Ku band, Ka band, and C band. X and S Bands. Previously Up Converters were used but were less efficient as they used to convert 70 MHz intermediate frequency to C band or Ku band.

Many Block Upconverters use phase-locked loop local oscillators. They also require an external 10 MHz frequency reference in order to maintain the exact transmit frequency. The Block Upconverters used in remote locations are usually 2 or 4 W in the Ku band while 5 W in the C band. Usually the engineers send 10 MHz reference frequency on the same feedline as the primary carrier. In case of smaller BUCs direct current (DC) supply is fed over the feedline utilizing an internal DC block.

Generally, the Block Upconverters are used in conjunction with the low-noise block converters (LNB). Since BUC is the up-converting device, it makes up the “transmit” side of the system, on the other hand, LNB is the down-converting device, so it makes up the “receive” side.

VSAT (Very Small Aperture Terminal) system used for bidirectional access via satellite is the perfect example of the utilization of both BUC and LNB.

The BUC is a block-shaped device recognized when assembled with the LNB in association with an OMT (orthogonal mode transducer) to the feed-horn facing the reflector parabolic dish. They also might be rack mounted indoors or not co-located with the dish.

Rotary Joint

An important part of a radar antenna system is the rotary joint-it is used to connect two different parts of RF waveguide. The rotary joint must be capable of transmitting high, microwave power with a minimum loss.

The Rotary Joints can have the following styles of connection between waveguide port and rotational axis:

• U-style: Both waveguide ports at a right angle to the rotational axis.
• L-style: One waveguide port at a right angle and one in line.
• I-style: Both waveguide ports in line.

Advantages of Waveguide Rotary Joint are:

• High power maintaining capacity.
• Wide bandwidth.
• Different configurations.
• Availability of Multi-channel joints.

Types of Waveguide Rotary Joint

• Single channel
• Dual channel
• Multi-channel

Features

• 360° Continuous rotation
• Straight and right-angle ports available
• Low insertion loss
• 1.5– 20 GHz wideband operation

Applications:

• Mechanically scanned antennas
• Automatic test equipment (ATE)
• Axial ratio measurement

Description of Waveguide Rotary Joint

It is commonly used to scan any kind of antennas in radar and radmeter.

Input and Output ports are available in different positions like: io

• Straight to straight,
• Right angle to straight,
• Straight to right angle, and
• Right angle to right angle variations.
• An extended port available on the ends of the rim

Coupling is by means of flange to ensure good electrical and mechanical support, hence low radiation and internal reflection. The flange end of the unit is joined with the mounting disc, while the rotating side is free to move.

Raditek SSPA amplifiers use field-effect transistors to supply amplification at frequencies 1MHz to 96GHz. Solid State Power Amplifier (SSPA) were developed for use in the most sensitive applications, including Satellite Communications (satcom) Airborne, Radars and Terrestrial Communications including HF, VHF, Wi-Fi, microwave and milliwave point to point links

Advantages of SSPA

• High performance
• Reliability
• Cost-effective modes replacement in applications which are currently using Traveling Wave Tube Amplifiers.

RF of the Amplifiers

• A tuned amplifier that amplifies high-frequency signals used in radio communications is called a radio frequency amplifier, or RF amplifier.
• Pre-amplified and several parallel symmetric branches make up the RF input to the solid state power amplifier.
• SSPA combining many parallel amplifier sections results in built-in redundancy because of this distributed design.
• A current sense alarm indication can be monitored and fed to the RF SSPA controller.
• The amplified results of all the symmetric branches are added up in a combing network which routes the resultant high power to the output of the RF SSPA.

SSPA Amplifier GaAs and GaN

• Gallium Arsenide (GaAs) and Gallium Nitrate (GaN) are the basic SSPA amplifiers currently used. • These are the devices that do the actual amplification.
• GaAs has the best linearity whereas GaN has the best efficiency.
• Solid-State devices such as GaAs FETs, IMPATT diodes, Gallium Nitrate GaN IMFETS and many more devices are for Microwave Amplification.

Different models of SSPA Solid State Power Amplifiers

• Modules Family – 1 MHz to 96GHz
• 19″ Rack Mount Family – 1.5 MHz to 18 GHz
• SSPA HF and ISM Bands up to 5 Kilowatts
• Low Noise Amplifier (LNA)

RADITEK INC. Circulator and Isolator Primer

A circulator is a three port device. It is essentially a passive device, but can exhibit some characteristics that make it almost behave as if it were active. An isolator is a two port device having an input and an output, it is simply a circulator whose third port has been terminated.

Circulators and Isolators provide unique transmission paths, allowing RF energy to pass in one direction with little (insertion) loss, but with high loss (isolation) in the other direction.

An isolator can exist as Stripline, Coaxial, Microstrip, or Waveguide type, and can be rated for powers from milliwatts to Megawatts. Raditek can provide superb stripline isolators to 18GHz, and Microstrip to over 100 GHz.

A typical use of a circulator would be as a duplexer, connecting a transmitter to Port 1, antenna to port 2 and receiver to port 3. This provides simultaneous transmission and reception of signals.

A very common use is at the output of a power amplifier. Forward power is passed with a minimal insertion loss. Reverse power resulting from disconnect at the output (removing the connection to antenna), will (with no isolator installed) flow back to the output FET/LDMOS etc. and likely damage or destroy it/them. With the isolator installed, any reflected power will flow into the isolator’s load and be safely dissipated as heat (as long as the load is rated to handle the power, and is properly heat sunk, so that the load temperature stays <100 degree C). The 100 Watt loads and attenuators, for example, will typically derate to 0 Watts dissipation at 150 degree C.

Typical stripline parameters could be 0.25dB insertion loss, 22dB isolation and VSWR on the ports of 1.2:1 over a 5% percentage bandwidth. Size increases for greater bandwidths.

Optionally available are: High performance models for extended temperature (e.g. RI-SS) and very low intermodulation distortion (-U),

The Raditek isolators and circulators are believed to have the best performance in the marketplace, within constraints and compromises of physical size, power, and RF performance.

Cavity diplexers are three port devices used in Tranceivers (transmitter and receiver) to separate the Transmitter frequency band from the receiver frequency band. They share a common antenna while working simultaneously at different frequencies. A diplexer is basically a high and a low pass filter connected to an antenna.

The transmitter part of the diplexer is different from the receiver in function its function is to filter out the transmitter sidebands that are generated ensuring the transmitter radiates within its allotted spectrum band and does not spill into adjacent frequency allocations. The receiver part of the diplexer is to protect the receiver from the overload on the transmitter. Diplexers are used on all duplex tranceivers covering all bands from high frequency to milliwave.

For example in a  wireless communication system. The diplexer is to receive the passband of 1710 MHz to 1785 MHz and a to transmit the passband of 1805 MHz to 1880 MHz. Providing the unusual passband and notch responses for the overcrowded mobile sites.

Applications: One of the applications of the diplexer is to connect the dual band mobile radio’s two antenna connection to a common feed line.

Raditek makes cavity diplexers from 30MHz to 60GHz in power ranges from milliwatts to kilowatts

A waveguide is a guided medium to transmit electromagnetic energy from one place to another. They usually operate in dominant mode. Also, they have cut off frequency, unlike two-wire transmission line. They support various modes.

Some of the components of waveguide are:

• • Load – This is responsible for absorbing microwave energy from the system
• • Tuner – This component is used to match the load impedance with the source impedance.
• • Isolator – They are circulators which have three ports and are responsible for transmitting microwave energy between the different ports while directing and reflecting energy to a port with an attached load.
• • Power Measuring (couplers)– These are the devices made to couple power taken from the waveguide system which helps in measuring power, frequency, and other parameters to ensure proper flow of energy.

Importance of Waveguide Components:

• • They are guided so there is no chance of leakage of energy.
• • They can handle high power.
• • They provide wide bandwidth.
• • They are strong in structure and durable as well.
• • They ensure the least amount of loss in a high-frequency application. Such as mm-wave application.
• • Inherently behaves as a high pass filter and many more.

Application of Waveguide Components:

• • Simply as a transmission line
• • A waveguide is also used to make various passive components like a filter, divider horn antennas, etc.
• • It can be used to measure and regulate high power.
• • It can also work at very high frequencies.

Waveguides have a crucial role to play in any microwave. Therefore, it becomes essential to check and select the waveguide that offers optimum performance and abides by safety standards.

Raditek waveguide components can be seen at https://raditek.com/Waveguide-Components.html

What does Linearity of an RF/Microwave amplifier mean?

It is one of the essential jobs of the amplifier. It is used to increase the power level of the input signal without having to alter the content of the incoming signal. This term ‘linearity’ is derived from the linear relationship between the input and output power. In an ideal amplifier, this would be related to the gain made by the amplifier.

However, it is not as easy as it sounds. It involves matching complex matching circuits to facilitate the flow from a low impedance of solid state to a higher impedance. But still, most amplifiers will have to suffer again roll off at the higher frequencies inevitably. In order to get high amplifier linearity, you will have to sacrifice on efficiency.

What deprives an amplifier of its linearity?

Amplifiers are not the ideal devices to have transfer characteristics, because they can generate harmonic signals multiple times the fundamental input signal. The intermodulation distortion also gets amplified along with it.

Non-linearity can also occur due to time. These non-linarites occur due to memory effects. It can happen when an input signal stresses the power supply voltage which results in creating input signal dependent non-linarites which are also known as the memory effects.

If anyone wants to extend transistor life and maintain good linearity, it is crucial to have thermal management for the microwave amplifier. It is because the linearity is dependent upon the temperature as cold or hot transistors exhibit different functions.

Raditek microwave amplifiers can be seen at http://raditek.com/AMPLIFIERS/Microwave-Amplifiers.htm

The RF Directional Coupler is an instrument for measuring or monitoring microwave power consisting of a line section which is inserted in any of the RF-lines. It could be coaxial lines, waveguides, tri-plate lines, wirelines, etc. The line is inserted between a transmitter or generator or amplifier and its load. It allows sampling of microwave energy without moving parts and adjusting. It is a simple and convenient means to do so.

Raditek Directional couplers are used for various applications that involve measurement, power monitoring, etc. A directional coupler can be used for isolating, eliminating or combining signals in microwave signal routing and RF. Coupled, Input, Transmitted and Isolated – are the four ports in a directional coupler.

The distinguishing features of directional couplers can be listed as coupling, insertion loss, mainline and auxiliary line, directivity, power handling capability, bandwidth, frequency sensitivity, etc. There are various types of directional couplers which have different sampling capabilities like coaxial directional coupler, dual directional coupler, Hybrid couplers, Bethe-hole coupler, Multi-hole coupler, etc.

Coaxial Coupler

One of the various types of the directional coupler is a Coaxial Coupler. They are usually used at frequencies ranging from 10 MHz to 40 GHz. They are commonly designed for low Voltage Standing Wave Ratio (VSWR) and insertion loss, high directivity, and flat coupling level.

They are suitable for 49GB systems, and some of its applications include general purpose test and measurement systems. There are two designs in the coaxial directional coupler – single-ended and dual directional.

The design of a single-ended coaxial directional coupler has the general appearance of a section of the coaxial line, with a second parallel section of line with one terminated end. The dual-directional coaxial coupler consists of two single-ended directional couplers connected back-to-back. They are used to allow measurement of forward and reflected power levels.

Applications

There is a varied range of applications for directional couplers. It is used as power sampler in measurement systems. It is commonly used for measuring and monitoring microwave power. It is also used for measuring and monitoring of frequency in operating systems.

One can guarantee constant conditions for physical, thermal or chemical process in the load as another application of the directional coupler is to use the signal of the forward wave for the regulation system to keep forward power constant. Directional reflectors can also be used for making use of isolation. In case isolation is high, they combine signals to feed a single line to a receiver.

Raditek couplers can be seen at https://raditek.com/smt-quadhybrid.htm