Quantcast NAVY FREQUENCY BAND USE

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
Table 1-1.-Radio-Frequency Spectrum NAVY FREQUENCY BAND USE Table 1-1 shows the radio-frequency spectrum broken down into bands that are used by the military. Each band of frequencies has its own characteristics. Navy Electricity and Electronics Training Series, Module 17, Radio-Frequency Communications Principles, discusses all the bands. This chapter will only discuss the bands that are of interest to the Aviation Electronic Technician. VLF and LF Band Communications The very low frequency (VLF) and low frequency (LF) bands were originally used for radio telegraphy. Because the wavelengths were in the kilometer range and higher (30 kHz has a wavelength of 10 kilometers, or about 6.2 miles), enormous antennas had to been used. With today’s technology, this is no longer a factor. MF and HF Band Communications The medium-frequency (MF) and high-frequency (HF) bands are not only used by the Navy, but portions are also used by commercial AM broadcasting stations. These spectrums also include the international distress frequencies (500 kHz, 2182 kHz, 8364 kHz, 3023.5 kHz and 5680 kHz). Signal radiation in these frequency ranges have the important property of being reflected by the ionosphere. The ionosphere is a layer of electrically charged particles at the top of the earth’s atmosphere. The layer is caused by the strong solar radiation entering the upper atmosphere. When a radio wave in the MF or HF range hits this layer, it is reflected back to earth. Multiple reflections between this layer and earth are are possible, allowing great distances to be obtained in these ranges, particularly the high-frequency band. The disadvantage of this type of propagation is that it depends on the characteristics of the ionosphere, which varies widely, especially during daylight hours. As a result of this varying, the waves are reflected differently and take different paths over a period of time. This causes the signal at the receiver to vary in strength, which causes the output to fade in and out. VHF and UHF Band Communications Signal radiation in these frequency ranges get very little ionospheric reflection. As a result, communi- cations in these ranges tend to be line-of-sight and over a short distance. Line-of-sight means exactly what the name says–the transmitter and receiver must be within a straight visual sighting line from each other. Buildings and uneven terrain may affect the transmission. The lower part of the UHF band and the VHF band is also used for mobile communications and television. 1-2



Aviation News
Didier Evrard, Head of Programmes at Airbus, has been awarded the 2015 Icare prize
This prize distinguishes him for his key role in the...
airbus.com
FAA Streamlines COAs for UAS Test Sites
The Federal Aviation Administration has made it simpler for the...
faa.gov
NextGen's Next Big Thing
May 21- As we move into the summer thunderstorm season,...
faa.gov
FAA Expands "Lessons Learned" Safety Website
May 21- The Federal Aviation Administration (FAA) recently added six...
faa.gov
Volaris takes delivery of first two A321s
First airline in Mexico to operate Airbus’ largest single-aisle aircraft...
airbus.com
Sichuan Airlines receives its 100th Airbus aircraft
China’s largest all Airbus operator celebrates a land-mark delivery Share...
airbus.com
Airbus and Aerospace Valley foster eco-innovation
Partnership with Small & Medium Enterprises Share this Read more...
airbus.com
Airbus helps airlines further improve their environmental performance
Launches the Sustainable Aviation Engagement Programme Share this Read more...
airbus.com
ACSS T3CAS Surveillance System Sees Airbus ADS-B Certification
ACSS T3CAS. Photo: ACSS [Avionics Today 05-15-2015] L-3 and Thales...
aviationtoday.com
Rockwell Collins Scores NASA Contract to Develop Sonic Boom Cockpit Display
NASA’s initial depiction of sonic boom footprint integrated with real-time,...
aviationtoday.com
UH-1Y Recovery Efforts to Resume
@font-face { font-family: "Arial"; }@font-face { font-family: "MS 明朝"; }@font-face...
aviationtoday.com
VivaAerobus receives first of 52 A320s on order
New A320 marks next step towards fleet renewal for Mexico’s...
airbus.com
FAA Kicks Off "No Drone Zone" Effort for D.C. Area
May 13 As hundreds of thousands of tourists flock to...
faa.gov
TAM’s first A350 XWB takes shape
The first A350-900 for TAM Airlines is progressing well in...
airbus.com
Airbus BizLab business accelerator invites first project entries
Six month support to convert innovative ideas into valuable business...
airbus.com
Bird-deterring drones and game consoles inspire the future of flight
Student ideas in final race for €30,000 Airbus biennial Fly...
airbus.com
Boeing Looks to Turn Backlog into Growth
[Avionics Today 05-13-2015] At the 2015 Boeing Investor’s Conference on...
aviationtoday.com
Russian Helicopters Fly on Anniversary of End of WWII's Eastern Front
On Saturday, Russian Helicopters' Mi-26, Mi-28N Night Hunter, Mi-35M, Ka-52...
aviationtoday.com
Airbus Reports Fatal Accident Involving A400M Test Aircraft
Airbus A400M aircraft. Photo: Wikipedia [Avionics Today 05-12-2015] Airbus Defense...
aviationtoday.com
SH-60B Sea Hawk Helicopter Receives Sundown Ceremony from US Navy
Today, May 11, at 3:30 p.m. Eastern, at Naval Air...
aviationtoday.com


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +