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IEEE 802.15.4 HRP UWB
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High pulse repetition frequency ultra-wideband (HPR UWB) is one of the physical layers defined for low data rate personal area network (LR-WPAN) communications in the IEEE 802.15.4 standard.
According to the FiRa Consortium:
"In challenging environments, such as parking structures, hospitals, airports and high density venues, ultra-wideband (UWB) technology outperforms other technologies in terms of accuracy, power consumption, robustness in wireless connectivity, and security, by a wide margin.
"UWB securely determines the relative position of peer devices with a very high degree of accuracy and can operate with line of sight at up to 200 meters. In contrast to narrow band wireless technologies, the use of wide bandwidth means UWB provides very stable connectivity, with little to no interference and offers highly precise positioning, even in congested multi-path signal environments.
"By calculating precise location, fine ranging based on UWB is a more secure approach to closing and opening locks, whether those locks are installed on a car door, a warehouse entryway, a conference room, or your front door."
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Frequencies |
Frequency | Bandwidth | Use | Service | Table |
499.2 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 0 | - | - |
3494.4 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 1 | - | - |
3993.6 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 2 | - | - |
3993.6 MHz | 1.3312 GHz | 802.15.4 HRP UWB Channel 4 | - | - |
4492.8 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 3 | - | - |
6489.6 MHz | 1.0816 GHz | 802.15.4 HRP UWB Channel 7 | - | - |
6489.6 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 5 | - | - |
6988.8 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 6 | - | - |
7488 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 8 | - | - |
7987.2 MHz | 1.3312 GHz | 802.15.4 HRP UWB Channel 11 | - | - |
7987.2 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 9 | - | - |
8486.4 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 10 | - | - |
8985.6 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 12 | - | - |
9484.8 MHz | 1.35497 GHz | 802.15.4 HRP UWB Channel 15 | - | - |
9484.8 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 13 | - | - |
9984 MHz | 499.2 MHz | 802.15.4 HRP UWB Channel 14 | - | - |
Associated Files:
![](wiki/Graphics/7e806835-6bda-49ce-8b62-0d9631fda4be.png) 802.15.4 HRP UWB PHY band allocation
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Radiosondes
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According to the U.S. National Weather Service:
In order to understand the dynamic processes that result in the weather we experience, we need to know what is happening through the entire atmosphere. These observations are primarily taken with the aid of radiosondes.
The radiosonde is a small instrument package that is suspended below balloon filled with either hydrogen or helium. As the radiosonde is carried aloft, it measures pressure, temperature, and relative humidity.
These sensors are linked to a battery-powered radio transmitter that sends the information to a ground receiver. By tracking the position of the radiosonde in flight via GPS (Global Positioning System), measurements of wind speed and direction aloft is also obtained.
Worldwide, most radiosonde observations are taken daily at 00Z and 12Z (6 a.m. and 6 p.m. EST). With worldwide coordination of these upper air observations, we can obtain a picture of the various pressure and wind patterns across the globe.
Radiosonde observations technically provide only pressure, temperature, and relative humidity data; the tracked position of a radiosonde is actually called a rawinsonde observation and is used to obtain wind speed and direction. However, meteorologists and other data users frequently refer to them as part of the radiosonde observation.
The radiosonde flight can last in excess of two hours, and during this time the radiosonde can ascend to over 115,000 feet (35,000 m) and drift more than 125 miles (200 km) from the release point. During the flight, the radiosonde is exposed to temperatures as cold as -130°F (-92°C) and air pressures of only a few hundredths of what is found on the Earth's surface.
When the balloon has expanded beyond its elastic limit (20-25 feet in diameter) and bursts, the radiosonde returns to Earth via a small parachute. This slows its descent, minimizing the danger to life and property.
If found, radiosondes are safe to handle, as long as the balloon is deflated. Cut the string to the balloon/parachute and place them in a trash receptacle. You may also dispose of the radiosonde itself or keep it.
Worldwide, there are about 1,300 upper-air stations. Observations are made by the NWS at 92 stations: 69 in the conterminous United States, 13 in Alaska, nine in the Pacific, and one in Puerto Rico.
NWS supports the operation of 10 other stations in the Caribbean. Through international agreements, data are exchanged between countries worldwide.
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Frequency Bands |
Band | Use | Service | Table |
400.15 - 406 MHz | Radiosondes | Meteorological Aids | F |
1675 - 1685 MHz | Radiosondes | Meteorological Aids | F |
Associated Files:
![](wiki/Graphics/33f51623-0869-45b1-8b62-bbd6fc56a7fd.jpg) A Lockheed Martin Mark IIA Microsonde (radiosonde).
![](wiki/Graphics/50effb20-1da5-4f04-854a-2b9bc51ba05d.jpg) Preparing to launch a radiosonde (Reno, NV area).
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Instrument Landing System
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Pilots use various radio aids to help guide them to the runway for landing, particularly in poor weather or other low-visibility conditions. Collectively, these aids are referred to as the Instrument Landing System (ILS). ILS utilizes 75 MHz, 108.1-111.95 MHz, and 329.15-335.0 MHz. According to NTIA, "there is international agreement within the International Civil Aviation Organization (ICAO) establishing the ILS as a standard landing system, and the ILS is used extensively worldwide."
Localizer
The localizer helps establish the proper horizontal path for an approach to the runway. The localizer transmission consists of two signals, one modulated with a 90 Hz tone and transmitted with a beam pointed along the left side of the approach, and another modulated with a 150 Hz tone and transmitted with a beam pointed along the right side of the approach. The plane's ILS receiver compares the strength of the two modulated tones and can determine whether the plane is aligned too far left (too much 90 Hz tone), too far right (too much 150 Hz tone), or along the center of the runway (equal strengths for both tones).
The localizer signal is useful for a distance of approximately 18 nm from the runway.
The localizer and glide slope frequencies are paired, so that the pilot need only select one, and the other is set automatically. The localizer channels are in the 108.1-111.95 MHz band. Note that the localizer channels are interspersed with channels for VHF Omnidirectional Range (VOR) signals in this band. VORs are used for enroute navigation, as opposed to precision navigation to the runway. See the related links for a full list of the ILS channel plan.
Glide Slope
The glide slope indicator works similarly to the localizer signal, but instead of indicating proper horizontal position, it indicates the proper vertical path to the runway (typically a 3 deg slope down to the runway). The 90 Hz tone is transmitted pointed above the proper path, while the 150 Hz modulated signal is pointed below the proper path. Comparison of the strength of the two tones informs the ILS receiver (and pilot) whether the plane is on the correct vertical path.
The glide slope signal is useful out to a distance of about 10 nm from the runway.
The glide slope and localizer frequencies are paired, so that the pilot need only select one, and the other is set automatically. The glide slope channels are in the 329.15-335.0 MHz band.
See the related links for a full list of the ILS channel plan.
Marker Beacons
The Instrument Landing System (ILS) marker beacons are located at varying distances along the approach to a runway to indicate the approximate distance to the runway. Marker beacons are typically used when an airport does not have Distance Measurement Equipment (DME) capabilities.
Outer markers are located between about 4-7 miles from the end of the runway. The antenna system, typically two yagis in a V configuration with the open part of the V pointing upwards, creates a narrow vertical beam that the pilots receive when they fly over. The outer marker transmits an AM signal at 75 MHz with a 400 Hz modulated tone.
The middle marker is typically about 2000 ft from the end of the runway, and transmits a 1 kHz modulated tone. The middle marker beacon is often a simple three-element yagi pointed straight up.
The inner marker is typically 700-800 ft from the end of the runway and transmits a 3 kHz modulated tone.
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Frequencies |
Frequency | Bandwidth | Use | Service | Table |
75 MHz | 400 kHz | Instrument Landing System outer, middle, and inner markers | Aeronautical Radionavigation | - |
Frequency Bands |
Band | Use | Service | Table |
108.1 - 111.95 MHz | Instrument Landing Systemn localizer signal | Aeronautical Radionavigation | - |
329.15 - 335 MHz | Instrument Landing System glide slope signal | Aeronautical Radionavigation | - |
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Defense Satellite Communication System 3 (DSCS III)
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According to the U.S. Space Force:
Defense Satellite Communications System (DSCS) constellation provides long haul communications to users worldwide through contested environments.
DSCS supports: the defense communications system, the military’s ground mobile forces, airborne terminals, ships at sea, and Department of Defense (DOD).
The first DSCS III satellite was launched in October 1982. The final DSCS III satellite, B6, was launched in August 2003. In all, DSCS III successfully launched 14 satellites, six of which are still operational and continue to be used in various capacities, from operational communications in Southwest Asia to research and development of ground-based support capabilities.
Space and Missile Systems Center (SMC), Los Angeles Air Force Base, Calif., sustains the DSCS Space Segment contract.
DSCS III satellites support globally distributed DOD and national security users. Modifications made to these satellites will provide substantial capacity improvements through higher power amplifiers, more sensitive receivers, and additional antenna connectivity options. The DSCS communications payload includes six independent Super High Frequency (SHF) transponder channels. Three receive and five transmit antennas provide selectable options for Earth coverage, area coverage and/or spot beam coverage. A special purpose single-channel transponder is also on board.
DSCS satellites provide the capabilities needed for effective implementation of worldwide military communications. It can adapt rapidly to dynamic operating conditions and perform under stressed environments. DSCS operates with large or small terminals. DSCS’s independent channels group users by operational needs or geographical location by allocating receiver sensitivity and transmitter power, thus providing maximum efficiency.
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Paired Frequency Bands |
Paired Bands | Use | Service | Table |
7250 - 7750 MHz | DSCS III downlink | Mobile-satellite | F |
7900 - 8400 MHz | DSCS III uplink | Mobile-satellite | F |
Frequencies |
Frequency | Bandwidth | Use | Service | Table |
7600 MHz | - | DSCS III Beacon (A series satellites) | Mobile-satellite | F |
7604.705882 MHz | - | DSCS III Beacon (B series satellites) | Mobile-satellite | F |
8005.146484 MHz | - | DSCS III Channel 1 command uplink | Mobile-satellite | F |
8370.146484 MHz | - | DSCS III Channel 5 command uplink | Mobile-satellite | F |
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Airport Surveillance Radar (ASR-11)
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According to the FAA:
Airport Surveillance Radar (ASR-11) is an integrated primary and secondary radar system that has been deployed at terminal air traffic control sites. It interfaces with both legacy and digital automation systems and provides six-level national weather service calibrated weather capability that provides enhanced situational awareness for both controllers and pilots.
The primary surveillance radar uses a continually rotating antenna mounted on a tower to transmit electromagnetic waves that reflect, or backscatter, from the surface of aircraft up to 60 nautical miles from the radar. The radar system measures the time required for radar to echo to return and the direction of the signal. From this, the system can then measure the distance of the aircraft from the radar antenna and the azimuth, or direction, of the aircraft in relation to the antenna. The primary radar also provides data on six levels of rainfall intensity and operates in the range of 2700 to 2900 MHz. The transmitter generates a peak effective power of 25 kW and an average power of 2.1 kW. The average power density of the ASR-11 signal decreases with distance from the antenna. At distances of more than 43 feet from the antenna, the power density of the ASR-11 signal falls below the maximum permissible exposure levels established by the Federal Communications Commission (FCC).
The secondary surveillance radar uses a second radar beacon antenna attached to the top of the primary radar antenna to transmit and receive area aircraft data for barometric altitude, identification code, and emergency conditions. Military, commercial, and some general aviation aircraft have transponders that automatically respond to a signal from the secondary radar by reporting an identification code and altitude. The air traffic control centers uses this system data to verify the location of aircraft within a 60-mile radius of the radar site. The secondary radar also provides rapid identification of aircraft in distress. The secondary radar operates in the range of 1030 to 1090 MHz. Transmitting power ranges from 160 to 1500 watts.
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Frequency Bands |
Band | Use | Service | Table |
1030 - 1090 MHz | Airport Surveillance Radar (ASR-11) secondary radar band | Aeronautical Radionavigation | F |
2700 - 2900 MHz | Airport Surveillance Radar (ASR-11) primary radar band | Aeronautical Radionavigation | F |
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