A new multichannel teletype terminal for use on long-range high-frequency radio systems

The modeling features of high-frequency amplifiers are considered. The urgency of the development of such amplifiers is justified and the application areas are indicated. The stages of design of amplifiers are described in detail.

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LONG DURATION ECHOES FROM AURORA, METEORS, AND IONOSPHERIC BACK-SCATTER

Canadian Journal of Physics ◽

10.1139/p53-017 ◽

1953 ◽

Vol 31 (2) ◽

pp. 171-181 ◽

Cited By ~ 25

Author(s):

D. W. R. McKinley ◽

Peter M. Millman

Keyword(s):

Long Range ◽

High Frequency ◽

The Other ◽

Very High Frequency ◽

Long Duration ◽

E Region ◽

Very High ◽

Visual Observations

In the course of the Ottawa meteor program some unusual echoes have been detected on 33 Mc. Echoes from the aurora are discussed and correlated with visual observations. Two mechanisms of radio reflections from the aurora have been proposed but the data here presented are insufficient to favor one over the other. On Aug. 4, 1948, six extremely long duration meteor echoes were observed which may have been due to abnormal ionospheric conditions. From time to time since August, 1948, a weak semipermanent echo has been recorded, usually appearing at a range of about 80 km., and enduring up to an hour. It is suggested that this echo is due to back-scatter from the same sources in the lower E-region that are presumed to be responsible for long-range very high frequency propagation.

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Variability and Performance of Short to Long-Range Single Baseline RTK GNSS Positioning in Indonesia

E3S Web of Conferences ◽

10.1051/e3sconf/20199401012 ◽

2019 ◽

Vol 94 ◽

pp. 01012 ◽

Cited By ~ 1

Author(s):

Irwan Gumilar ◽

Brian Bramanto ◽

Fuad F. Rahman ◽

I Made D. A. Hermawan

Keyword(s):

Long Range ◽

High Frequency ◽

Carrier Phase ◽

Satellite System ◽

High Accuracy ◽

Gnss Positioning ◽

And Performance ◽

Gnss Network ◽

Single Baseline ◽

Global Navigation Satellite

As the modernized Global Navigation Satellite System (GNSS) method, Real Time Kinematic (RTK) ensures high accuracy of position (within several centimeters). This method uses Ultra High Frequency (UHF) radio to transmit the correction data, however, due to gain and power issues, Networked Transport of RTCM via Internet Protocol (RTCM) is used to transmit the correction data for a longer baseline. This Research aims to investigate the performance of short to long-range single baseline RTK GNSS (Up to 80 KM) by applying modified LAMBDA method to resolve the ambiguity in carrier phase. The RTK solution then compared with the differential GNSS network solution. The results indicate that the differences are within RTK accuracy up to 80 km are several centimeter for horizontal solution and three times higher for vertical solution.

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Radio Systems for Long-Range Navigation

Aerospace Navigation Systems ◽

10.1002/9781119163060.ch3 ◽

2016 ◽

pp. 109-140 ◽

Cited By ~ 1

Author(s):

Anatoly V. Balov ◽

Sergey P. Zarubin

Keyword(s):

Long Range ◽

Radio Systems

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Indoor Vehicles Geolocalization Using LoRaWAN

Future Internet ◽

10.3390/fi11060124 ◽

2019 ◽

Vol 11 (6) ◽

pp. 124 ◽

Cited By ~ 6

Author(s):

Pietro Manzoni ◽

Carlos T. Calafate ◽

Juan-Carlos Cano ◽

Enrique Hernández-Orallo

Keyword(s):

Long Range ◽

High Frequency ◽

Area Network ◽

Navigation Satellite ◽

Wide Area Network ◽

Heavy Vehicles ◽

Solid Materials ◽

Industrial Setting ◽

Indoor Geolocation ◽

Global Navigation Satellite

One of the main drawbacks of Global Navigation Satellite Sytems (GNSS) is that they do not work indoors. When inside, there is often no direct line from the satellite signals to the device and the ultra high frequency (UHF) used is blocked by thick, solid materials such as brick, metal, stone or wood. In this paper, we describe a solution based on the Long Range Wide Area Network (LoRaWAN) technology to geolocalise vehicles indoors. Through estimation of the behaviour of a LoRaWAN channel and using trilateration, the localisation of a vehicle can be obtained within a 20–30 m range. Indoor geolocation for Intelligent Transporation Systems (ITS) can be used to locate vehicles of any type in underground parkings, keep a platoon of trucks in formation or create geo-fences, that is, sending an alert if an object moves outside a defined area, like a bicycle being stolen. Routing of heavy vehicles within an industrial setting is another possibility.

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