scholarly journals Calculating the probability of detecting radio signals from alien civilizations

2006 ◽  
Vol 5 (2) ◽  
pp. 143-149 ◽  
Author(s):  
Marko Horvat
Keyword(s):  
Radio Signal ◽  
Radio Communications ◽  
Radio Emissions ◽  
Starting Point ◽  
Radio Signals

Although it might not be self-evident, it is in fact entirely possible to calculate the probability of detecting alien radio signals by understanding what types of extraterrestrial radio emissions can be expected and what properties these emissions can have. Using the Drake equation as the obvious starting point, and logically identifying and enumerating constraints of interstellar radio communications, may yield the possibility of detecting a genuine alien radio signal.

Cognitive Wireless Communications – A paradigm shift in dealing with radio resources as a prerequisite for the wireless network of the future – An overview on the topic of cognitive wireless technologies

Frequenz ◽  
2016 ◽  
Vol 70 (7-8) ◽  
Author(s):  
Thomas Haustein ◽  
Slawomir Stanczak ◽  
Adam Wolisz ◽  
Friedrich Jondral ◽  
Hans Schotten ◽  
...  
Keyword(s):  
Wireless Communications ◽  
Wireless Communication ◽  
Mobile Network ◽  
Radio Spectrum ◽  
Wireless Channel ◽  
Radio Communications ◽  
Communications Systems ◽  
Starting Point ◽  
The Status ◽  
Wireless Communications Systems

AbstractWireless radio communications systems form the basis for mobile network connections in the digital society. A limited amount of radio spectrum and a spatially densified use of wireless communications systems require a resource-efficient use of the spectrum. Mechanisms of cognitive radio may hold the key to a more efficient use of the available spectrum under consideration of quality of service requirements. These mechanisms take advantage of location-specific knowledge of the wireless channel occupation in the dimensions of frequency, time, location and direction in space and therefore enable co-existent and reliable wireless communication. The authors give an introduction to the status of cognitive wireless communication technology, which represents the starting point of a series of research projects promoted by BMBF during 2012–2014.

Guglielmo Marconi and Radioastronomy

1996 ◽  
Vol 175 ◽  
pp. 1-4
Author(s):  
Giancarlo Setti
Keyword(s):  
Antenna Array ◽  
Radio Signal ◽  
Rapid Development ◽  
100Th Anniversary ◽  
Direct Link ◽  
Radio Communications ◽  
Guglielmo Marconi ◽  
Great Discovery ◽  
First Time

The decision to hold this IAU Symposium at Bologna on the occasion of the 100th anniversary of the discovery of the wireless telegraphy represents in itself a recognition of the widespread feeling of a historical link between the great discovery of Guglielmo Marconi and the birth of radioastronomy. Obviously, it is not a direct link. We all well know that the birth of radioastronomy must be traced back to the year 1932 when Karl Jansky recognized for the first time the existence of a radio signal probably associated with a celestial source. This a classical example of a ‘serendipitous’ discovery made while Jansky was investigating for the Bell Telephone Laboratories the sources of radio interferences with a rotating antenna array operating at about 14 m wavelength. The study of local disturbances was of primary importance in the rapid development of radio communications which had been geared by the Marconi's discovery.

RADIO FADING AND THE NATURAL ELECTROMAGNETIC BACKGROUND

1965 ◽  
Vol 43 (11) ◽  
pp. 1951-1961 ◽  
Author(s):  
H. J. Duffus ◽  
G. M. Boyd ◽  
J. K. Kinnear
Keyword(s):  
Radio Signal ◽  
Spectral Component ◽  
Broad Band ◽  
Auroral Zone ◽  
Frequency Range ◽  
Single Station ◽  
D Region ◽  
Radio Signals ◽  
Signal Fluctuation ◽  
The Difference

A comparison is made between the natural geomagnetic background in the frequency range 0.006–0.6 Hz and fluctuations of the difference in received signal strength between the two magnetoionic modes of vertically incident broad-band radio signals in the range 6–16 MHz, observed at a single station near Victoria, British Columbia. At this station the following points were observed:1. During the daytime there is often a spectral component common to the radio-signal fluctuations and to the natural geomagnetic background, even during quiet magnetic times. There is seldom phase coherence, however, except for a few minutes at a time.2. There is a small but highly significant (1%) linear correlation R = 0.33 between all the hourly mean amplitudes of the radio-signal fluctuation level and the hourly mean amplitudes of the natural geomagnetic background. The correlation coefficient rises as high as R = 0.71 at 1400–1500 local time, when only a particular hour of each day is considered. It is concluded that geomagnetic micropulsations in this frequency range are a better indicator of r-f. fluctuations than is the local Kp.3. At night, there is a relationship between the occurrence of Pt's and of r-f. fluctuation, although their frequency components are not usually as closely related as are those of the daytime regimes.It is suggested that geomagnetic micropulsations can couple exospheric or auroral zone fluctuations into the upper E or F regions strongly enough to produce observable radio-signal fluctuations at mid-latitudes, even during magnetically quiet times.Lack of correlation between micropulsations and phase fluctuations of 18 kHz signals observed over an E–W 100-km path, and 80 kHz observed over an E–W 3 300-km path suggests that significant coupling does not extend down to the D region during magnetically quiet times.

On the characterization of VLF radio signal propagation in atmosphere in quite solar conditions

2020 ◽  
Author(s):  
Giovanni Nico ◽  
Aleksandra Nina ◽  
Anita Ermini ◽  
Pierfrancesco Biagi
Keyword(s):  
Radio Signal ◽  
Technological Development ◽  
Low Frequency ◽  
Lower Ionosphere ◽  
Signal Propagation ◽  
Temporal Variations ◽  
Seasonal Effects ◽  
Propagation Mode ◽  
Theory Approach ◽  
Radio Signals

<p>In this work we use Very Low Frequency (VLF) radio signals, having a frequency in the bands 20-80 kHz, to study the VLF signal propagation in the atmosphere quite undisturbed conditions by selecting the signals recorded during night. As a good approximation, we can model the propagation of VLF radio signals as characterized by a ground-wave and a sky-wave propagation mode. The first one generates a radio signal that propagates in the channel ground-troposphere, while the second one generates a signal which propagates using the lower ionosphere as a reflector. The VLF receivers of the INFREP (European Network of Electromagnetic Radiation) network are used. These receivers have been installed since 2009 mainly in southern and central Europe and currently the INFREP network consists of 9 receivers. A 1-minute sampling interval is used to record the amplitude of VLF signals. Long time-series of VLF signals propagating during night are extracted from recorded signals to study possible seasonal effects due to temporal variations in the physical properties of troposphere. A graph theory approach is used to investigate the spatial correlation of the aforementioned effects at different receivers. A multivariate analysis is also applied to identify common temporal changes observed at VLF receivers.</p><p>This work was supported by the Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR), Italy, under the project OT4CLIMA. This research is supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia, under the projects 176002 and III44002.</p>

scholarly journals ANALYSIS OF THE PARAMETRIC SENSITIVITY OF THE METHOD FOR OPTIMIZING THE STRUCTURE OF SPECTRALLY EFFECTIVE RADIO SIGNALS

T-Comm ◽  
2021 ◽  
Vol 15 (3) ◽  
pp. 50-58
Author(s):  
Sergei S. Pechnikov ◽  
◽  
Sergey A. Sherstyukov ◽  
Keyword(s):  
Power Amplifiers ◽  
Spectral Efficiency ◽  
Output Signal ◽  
Phase Modulation ◽  
Communication Systems ◽  
Phase Shifters ◽  
Radio Communications ◽  
Parametric Sensitivity ◽  
Radio Signals ◽  
Vector Modulation

Currently, increasing the speed of information transmission in wireless communication networks is a topical issue. The growing demand for spectral efficiency in radio communication systems gives rise to the introduction of signals with amplitude-phase modulation. Despite all its advantages, signals with vector modulation are characterized by a change in the envelope, which makes it impossible to use highly efficient nonlinear power amplifiers. Energy efficiency is clearly a critical factor in portable radio communications systems, where power supplies are often used in small packages, and the presence of energy losses due to heat dissipation is a significant drawback that requires additional cooling systems. In this connection, when developing modern radio communications, radio engineers are faced with the contradictory task of achieving maximum energy and spectral efficiency. One of the approaches to reduce nonlinear distortion of vector modulation is the use linearization schemes for nonlinear power amplifiers. This work is devoted to increasing the energy and spectral efficiency of signals with amplitude-phase modulation. The article discusses the restrictions imposed on the input signals for the method for optimizing of structure of spectrally effective radio signals with vector modulation, the formation of the output signal, the influence of phase shifters phase imbalance on p/2, the index of balance modulation, and the analysis of parametric sensitivity. The possibility of using quadrature modulators to form components with phase modulation and constant envelope is considered. This method was simulated and the effect of phase imbalance on the shape of the output signal constellation was revealed.

scholarly journals Study of Brain Radio Signals Using Bispectral Analysis

2021 ◽  
pp. 138-141
Author(s):  
B. A. Hovhannisyan
Keyword(s):  
Human Brain ◽  
Radio Signal ◽  
Emotional States ◽  
Bispectral Analysis ◽  
Spectral Components ◽  
Radio Signals ◽  
Sensor Probe

Using a special sensor (probe antenna-applicator), radio signals emitted by the human brain are recorded. The changes of different parameters are investigated while studying different physical and emotional states of people. The studies are carried out using spectral and bispectral analysis in the LabVIEW environment. It is shown that in a stressful state the bispectrum of the brain’s radio signal is significantly enriched, and many phase coupled spectral components appear. They undergo changes in their amplitude and frequency. The results of these studies may be useful for understanding the nature and identification of fast processes in the human brain.

scholarly journals The Deceleration of Radio/Light Transmission; A Collision Mechanism Dependent Radio Signal Emission, Transmission, and Reception

2021 ◽  
Author(s):  
Jing Zhang
Keyword(s):  
Light Transmission ◽  
Radio Signal ◽  
Slow Fading ◽  
Fast Fading ◽  
Before And After ◽  
Radio Signals ◽  
Electron Photon ◽  
The Relationship ◽  
Group Pattern ◽  
Collision Mechanism

Abstract The fast and slow fading of radio signal transmissions or laser beam itself and its spare light confirm the presence of two kinds of collisions --- electron-photon and photon-photon collision. Photon transmissions of radio signals are either in consecutive dense photon groups in slow fading process or widespread group pattern in fast fading form. The photon transmission shapes are irregular and dynamical changes. The radio frequency shift and the wavelength reduction by the calculation demonstrate decelerations of radio/light transmission speeds due to the gradual reduced distance between two consecutive photon groups along the transmission pathway. Photons from radio signals are able to affect electron movements in radio signal receiving process and electrons able to kick photons into space during radio signal emission. The pattern of free electron movement under the influence of local electromagnetic force in antenna is consistent with the randomly dynamic changes of radio signal in space. The fast fading is due to the collision of consecutive photon groups of signals in slow fading with free photons in space. The mathematical equation for the relationship between light/radio transmission speeds before and after photons collisions is established. The equation is confirmed by the calculations of well-known difference of light transmission speeds in different media. The gravities from Earth and Sun play little role during light/radio transmission.

scholarly journals The Deceleration of Radio/Light Transmission; A Collision Mechanism Dependent Radio Signal Emission, Transmission, and Reception

2021 ◽  
Author(s):  
Jing Zhang
Keyword(s):  
Light Transmission ◽  
Radio Signal ◽  
Slow Fading ◽  
Fast Fading ◽  
Before And After ◽  
Radio Signals ◽  
Electron Photon ◽  
The Relationship ◽  
Group Pattern ◽  
Collision Mechanism

Abstract The fast and slow fading of radio signal transmissions or laser beam itself and its spare light confirm the presence of two kinds of collisions --- electron-photon and photon-photon collision. Photon transmissions of radio signals are either in consecutive dense photon groups in slow fading process or widespread group pattern in fast fading form. The photon transmission shapes are irregular and dynamical changes. The radio frequency shift and the wavelength reduction by the calculation demonstrate decelerations of radio/light transmission speeds due to the gradual reduced distance between two consecutive photon groups along the transmission pathway. Photons from radio signals are able to affect electron movements in radio signal receiving process and electrons able to kick photons into space during radio signal emission. The pattern of free electron movement under the influence of local electromagnetic force in antenna is consistent with the randomly dynamic changes of radio signal in space. The fast fading is due to the collision of consecutive photon groups of signals in slow fading with free photons in space. The mathematical equation for the relationship between light/radio transmission speeds before and after photons collisions is established. The equation is confirmed by the calculations of well-known difference of light transmission speeds in different media. The gravities from Earth and Sun play little role during light/radio transmission.

scholarly journals Observation of radio emissions from electron beams using an ice target

2019 ◽  
Vol 216 ◽  
pp. 02010
Author(s):  
Keiichi Mase ◽  
Daisuke Ikeda ◽  
Aya Ishihara ◽  
Hiroyuki Sagawa ◽  
Tatsunobu Shibata ◽  
...  
Keyword(s):  
Light Source ◽  
Electron Beams ◽  
High Energy ◽  
Neutrino Telescope ◽  
South Pole ◽  
The South ◽  
Telescope Array ◽  
Radio Emissions ◽  
Systematic Uncertainties ◽  
Radio Signals

To observe high energy cosmogenic neutrinos above 50 PeV, the large neutrino telescope ARA is being built at the South Pole. The ARA telescope detects neutrinos by observing radio signals by the Askaryan effect. We performed an experiment using 40 MeV electron beams of the Telescope Array Electron Light Source to verify the understanding of the Askaryan emission as well as the detector responses used in the ARA experiment. Clear coherent polarized radio signals were observed with and without an ice target. We found that the observed radio signals are consistent with simulation, showing that our understanding of the radio emissions and the detector responses are within the systematic uncertainties of the ARAcalTA experiment which is at the level of 30%.

Measurement-based Statistical Method for Estimating and Verifying Signal Coverage and Coverage Probability in Urban Microcells

2018 ◽  
Vol 8 (6) ◽  
pp. 74
Author(s):  
Joseph Isabona ◽  
Kingsley Obahiagbon
Keyword(s):  
Outage Probability ◽  
Communication Networks ◽  
Coverage Probability ◽  
Statistical Approach ◽  
Radio Signal ◽  
Signal Strength ◽  
Signal Coverage ◽  
Radio Signals ◽  
Coverage Quality

Customer’s complaints and concerns about radio signal coverage at their home are important trigger to performance relevant drive test in the relevant area to observe the coverage quality. In this paper, statistical approach has been employed to assess the quality of the radio coverage and outage probability based on measured radio signals in an established UMTS network, operational in Ikoyi, a typical urban microcell in Nigerian environment. The results shows that the quality of radio signals at the cell edge is very poor in locations 2 and 4, as they recorded poor coverage probability performance of 89.25% and 81.72% and high outage probability performance of 10.74% and 18.28% respectively. It is also observed that the smaller the fade margin, the higher the outage probability and the lower the coverage reliability. This implies that the smaller the fade margin, the smaller the received signal strength at the MS and the more likely outage events. Hence, sufficient signal strength is needed at the mobile terminals at locations 2 and 4 in order to achieve the outage probability and coverage reliability required to effectively operate cellular communication networks.

Sign in / Sign up

Export Citation Format

Share Document