Wireless University: Broadcast, RF Industry Learning Center

Technical White Papers:

Technical Note 101 - High Power RF Interference to Cellular Radio Equipment
Do you have trouble getting test equipment to function properly, problems with power supply regulators, unexplainable hand-offs, dropped calls or other artifacts? Read this.

Technical Note 102 - Detuning Communications Towers Solves AM Reradiation Problem
The solution to interference between land mobile or microwave towers and AM antennas is often complex...LBA shows its experience.

Technical Note 103 - Gremlins In Your Cell Site?
The static and dropped calls that are haunting your customers may be coming from your cell site. Learn how to plan for effective RF interference abatement.

Technical Note 104 - High Power RF Interference - Part I
Many consumer cellular interference problems are traceable to cell or switching sites located near high power RF installations miles away. Here are some ideas.

Technical Note 105 - High Power RF Interference - Part II
More on high power RF interference - with an emphasis on AM Radio.

Technical Note 106 - Wireless Cable: A Competing Technology
While traditionally urban areas have been ideal settings for wireless cable, the medium also is becoming more popular in rural settings. Find out more about this technology.

Technical Note 107 - Cellular Packet Data EMI Considerations
The cellular industry is about to launch cellular digital packet data (CDPD). This technical note looks into some possible electromagnetic interference effects on CDPD technology implementation in existing cellular systems.

Technical Note 108 - AM Broadcasting: The New Cellular Design Factor
One lesser known factor involved in cellular modifications or construction is potential interference with AM antennas. Find out more about AM reradiation problems and site prescreening.

Technical Note 109 - Blowing the Whistle on RF Interference
Many of the “interference” problems plaguing communicators using cellular, PCS, microwave, satellite or other systems are traceable to events originating not within the communicator’s facility, but from proximity to broadcast or other high power RF installations. Find out how you can maintain a steady-state RF situation at any site.

Technical Note 110 - When RF Interference Strikes
Typically a wireless operator will raise or lower tower height, add radios or change system configurations in an attempt to eliminate service problems. These approaches do not work when EMI strikes. As the following three instances demonstrate, well-designed shielding systems provided cost-effective and lasting solutions.

Technical Note 113 - AM Broadcasting: The Overlooked Wireless Design Factor
As wireless systems have sprouted towers across the landscape, a seemingly unlikely conflict has arisen between wireless operators and old-fashioned AM broadcast stations. The FCC Rules state that all licensees must avoid interference with all AM broadcast stations. Furthermore, affected licensees must prove to the FCC that they have corrected all such problems. This must be done at their own expense.

Technical Note 114 - AM Colocation - It's Real!
Today, there are an estimated 10,000 AM towers in the United States, and they are virtually untapped resources for wireless base station sites. And, notwithstanding the mythology, AM colocation is both practical and efficient.

Technical Note 115 - Wireless Evolution, Definition and Current Practice
There are several over-the-air delivery systems for TV entertainment, including LPTV: Low Power TV, for example. By general agreement, the one broadcasting at microwave frequencies (2500-2700 MHz US 2300-2400 Australia) is known as "Wireless Cable".

Technical Note 116 - Wireless Options for Telecommunications Infrastructure Development
Wireless telecommunications, that is, telecommunications through the medium of radio waves, is rapidly emerging as the dominant force in development of infrastructure in emerging economies.

Technical Note 117 - A Primer on Foundation Wizard^TM Dispersive Wave Testing
Dispersive wave propagation is the name of an area of science which considers how wave motion in solid materials is affected by the mechanical properties and geometry (i.e., boundaries, discontinuities) of the material. Any strike to the surface of a solid creates a disturbance that propagates throughout the solid as a wave.

Technical Note 118 - A Primer on Diplexer/Triplexer Adjustment Procedures
An increasing number of Medium Wave (AM) diplexers and triplexers are being placed in service. The use of these devices to feed multiple transmitters to common antenna systems may be a cost effective way to minimize the substantial physical plant requirements of MW broadcast stations.

Technical Note 119 - AM Protection - Dealing with Legacy Towers
A significant number of wireless towers have changed hands; often without supporting documentation that AM protection measures have been taken to comply with the Federal Communications Commission Rules.

Technical Note 120 - Wireless Cable Comes Into the Twenty-First Century –
A Historical and Regulatory Overview
In 1963, the frequency band 2500-2686 MHz was reserved to educational institutions for over-the-air transmission of instructional TV programs. Transmission was point-to-point, for example, campus-to-campus or campus-to-hospital for continuing education needs...

Tecnical Note 120A: New Regulations for MDS and ITFS -
The 2002 WCA Proposal 2002
The Wireless Communications Association International, Inc., The National ITFS Association and the Catholic Television Network have presented a white paper to the FCC. That white paper is entitled “A Proposal for Revising the MDS and ITFS Regulatory Regime” and has been assigned FCC Docket Number DA 02-2732. Comments are due November 14, 2002 and reply comments are due November 21, 2002...

Technical Note 121: NAVTEX in the United States
The International Maritime Organization has designated NAVTEX as the primary means for transmitting coastal urgent marine safety information to ships worldwide.

Technical Note 122: U.S. Coast Guard DGPS
NAVCEN operates the Coast Guard Maritime Differential GPS (DGPS) Service and the developing Nationwide DGPS Service, consisting of two control centers and over 60 remote broadcast sites.

Technical Note 123: Gremlins in Your Medical Equipment
RF radiation is everywhere. We can't smell it, see it, hear it or touch it, yet we know it is out there. Medical diagnostic equipment provides unreliable results. Weird audio can be heard through testing equipment. Rock and roll music accompanies a medical diagnostic test. These gremlins are caused by high-power RF installations several miles away, such as AM, FM and shortwave radio, TV, microwave links and other such sources.

Technical Note 124: RF Shock and Burn: Radio Frequency Radiation
This note is a compilation of various research studies performed in the late1980s. This research was focused on the RFR levels and conditions that could cause electric shock or tissue burns. Several instruments were used and various frequency levels were tested. The results were differentiated between male and female responses. The results of these research studies were used by regulatory agencies to provide safe guidelines to radio frequency radiation. As with other research of this kind, the researchers suggested that further studies would be beneficial as more information was gleaned regarding shock and burn in humans.

Technical Note 125: Human Radio Frequency Exposure From SCADA Remote Sites
The public, workers, and risk managers often raise questions concerning human exposure to radio frequency (non-ionizing RF) energy that might be expected from proximity to antennas, such as at a remote SCADA site. This brief note will provide calculated exposure values and will relate them to U. S. Federal government maximum permitted exposure limits.

Technical Note 126: Is Your Facility RFGreen^®?
Electromagnetical energy is an environmental issue that is often overlooked. This invisible environmental factor should be considered as carefully as air and water quality.

Technical Note 127: Keeping Black Hat In The Box
Setting up an isolated, remotely-accessible, secure wireless equipment pod to allow even the most invasive and potentially destructive wireless lab exercises to be performed within an area that is physically adjacent to a wireless production network.

Application Notes:

Application Note 10 -
Tunipole Antenna Applications in Medium Frequency Broadcasting

Application Note 11 -
Component Safety Factors in Medium Wave Broadcasting

Application Note 13 -
The Combipole - A New Approach to Multiple MW Stations On One Tower

Application Note 15 -
Quick Determination of Medium Wave Coverage

Application Note 16 -
Quick Method of Finding "T" Network Values

Application Note 17 -
Medium Wave AM Antenna Goes Mobile

Application Note 18 -
RF Intermodulation Products

Application Note 19 -
RF Vector Impedance Meter Uses

Application Note 20 -
Technical Practices for LBA Technology AM Tuning Products