Antenna Tuner Circuits

  

 

An antenna tuner, transmatch, or antenna tuning unit (ATU) is a device connected between a radio transmitter or receiver and its antenna to improve the efficiency of the power transfer between them by matching the impedance of the equipment to the antenna. An antenna tuner matches a transceiver with a fixed impedance (typically 50 ohms for modern transceivers) to a load (feed line and antenna) impedance which is unknown, complex or otherwise does not match. 
 
For systems which need to operate over a wide frequency range such as a power amplifier operating over the range 1 MHz to 30 MHz in some solid state designs a series of wide band transformers wound on ferrite cores can be used. This design has the advantage of not requiring any tuning when the operating frequency is changed.  An ATU allows the use of one antenna for a broad range of frequencies.
 
An antenna plus matcher is never as efficient as a naturally resonant antenna due to additional induced losses on the feed line due to the SWR (multiple reflections), and losses in the ATU itself, although issues of pattern and capture area may outweigh this in practice. In solid state RF power amp design these networks are useful because MOSFETs and bipolar transistors are designed to operate with low resistance loads.
 
This type of design can also be used to match an antenna to a transmission line, it has the advantage of not requiring any tuning but it has the disadvantage of not being capable of fine adjustment. These networks can be used to extend the useful range of a conventional narrow band ATU. Valved RF amplifiers are very different because the load resistance which a valve is designed to operate with is normally much greater, hence for power designs the circuit designs are often very different.

 

 

News

Carrier Infrastructure in Telecom Applications Market Revenue and Value Chain 2014-2020

Satellite PR News (press release) Carrier Infrastructure in Telecom Applications Market Revenue and Value Chain 2014-2020 Satellite PR News (press release) The telecom industry infrastructure consists of many active...

Jan 20, 2017

Consumer Reports responds to MacBook Pro battery test controversy, stands by its findings

9 to 5 Mac Consumer Reports responds to MacBook Pro battery test controversy, stands by its findings 9 to 5 Mac At one point after viewing a google search result under Safari, the discrete GPU became active and...

Dec 29, 2016

SPS IPC Drives 2016 Exclusive Show Report

Drives & Controls SPS IPC Drives 2016 Exclusive Show Report Drives & Controls Turning to drives, Baumüller has introduced an intermediate- circuit unit for its b maXX 5000 converters, which can store brake energy in a...

Jan 9, 2017

New active antenna system improves beamforming and enables 5G communications

New active antenna system improves beamforming and enables 5G communications Electronics News The low-SHF band compatible AAS combines the antenna and RF components through the use of a newly developed high-density...

Feb 25, 2016

active antenna

Hackaday active antenna Hackaday There were no transistors or integrated circuits , and the tubes of the day could not produce high power outputs. Radio engineers back then had to employ other solutions ... closest...

Jun 27, 2016

NEC Develops 5G Massive-element Active Antenna System that Supports 28GHz Band

NEC Develops 5G Massive-element Active Antenna System that Supports 28GHz Band ACN Newswire (press release) TOKYO, Nov 16, 2016 - (JCN Newswire) - NEC Corporation (TSE: 6701) today announced that it has developed a...

Nov 16, 2016

Rogers Corporation Launches Cost-Effective Laminates For Automotive Radar Sensor Applications

Rogers Corporation Launches Cost-Effective Laminates For Automotive Radar Sensor Applications RF Globalnet (press release) Rogers Corporation announced the latest addition to its RO4000 Series thermoset circuit materials:...

Dec 14, 2016

Reality Check: Why active antenna systems are the superior antenna tuning solution

Reality Check: Why active antenna systems are the superior antenna tuning solution RCR Wireless News Given all of the benefits of antenna tuning, several vendors are now launching active impedance matching tuning...

Apr 17, 2013

Android Circuit: New Galaxy S7 Revealed, Galaxy Note 6 Improvements Leak, Android Beats Apple

Android Circuit : New Galaxy S7 Revealed, Galaxy Note 6 Improvements Leak, Android Beats Apple Forbes Taking a look back at seven days of news across the Android world, this week's Android Circuit includes the...

May 14, 2016

Grand Apple Patent Covers a Smart Chameleonic Apple Watch Band with 3D Touch, Liquid Cooling & More

Patently Apple Grand Apple Patent Covers a Smart Chameleonic Apple Watch Band with 3D Touch, Liquid Cooling & More Patently Apple Today, the U.S. Patent and Trademark Office published a patent application from...

Sep 22, 2016

Units & Modules