Radio Astronomy

Modern radio telescopes like the Square Kilometer Array (SKA) will need to process in real-time exabytes of radio-astronomical signals to construct a high-resolution map of the sky. Near-Memory Computing (NMC) could alleviate the performance bottlenecks due to frequent memory accesses in a state-of-the-art radio-astronomy imaging algorithm. In this paper, we show that a sub-module performing a two-dimensional fast Fourier transform (2D FFT) is memory bound using CPI breakdown analysis on IBM Power9. Then, we present an NMC approach on FPGA for 2D FFT that outperforms a CPU by up to a factor of 120x and performs comparably to a high-end GPU, while using less bandwidth and memory.

The signal processing firmware that has been developed for the Low Frequency Aperture Array component of the Square Kilometre Array (SKA) is described. The firmware is implemented on a dual FPGA board, that is capable of processing the streams from 16 dual polarization antennas. Data processing includes channelization of the sampled data for each antenna, correction for instrumental response and for geometric delays and formation of one or more beams by combining the aligned streams. The channelizer uses an oversampling polyphase filterbank architecture, allowing a frequency continuous processing of the input signal without discontinuities between spectral channels. Each board processes the streams from 16 antennas, as part of larger beamforming system, linked by standard Ethernet interconnections. These are envisaged to be 8192 of these signal processing platforms in the first phase of the SKA so particular attention has been devoted to ensure the design is low cost and low power.

Abstract
We still analyze Jupiter Data - the paper tries to answer the following questions: 
1. Why the three inner planets distances to Jupiter = their orbital circumferences but not accurately (with error 1%)?
Specifically
a. Venus Jupiter Distance 673 mkm = Venus orbital circumference 680 mkm
b. Earth Jupiter Distance 930 mkm = Earth orbital circumference 940 mkm (In this cases Earth and Jupiter should be at 2 different sides from the sun so 778.6 mkm +149.6 mkm = 930 mkm)
c. Mercury moves during its day period (175.94 solar days) a distance = 720.7 mkm= Mercury Jupiter distance 
2. Do these 3 planets define their orbital circumferences depend on their distances to Jupiter? If yes,  How?
3. Can Jupiter with the inner planets (including Mars) consist one system move together as a train carriages?
Paper Conclusions
I- There's A Light Velocity =1.16 mkm/Sec
II- Jupiter effects On The Inner Planets Periods Of Time

Gerges Francis Tawdrous +201022532292

Improving the of radio telescopes and ra- diometers and their associated receive subsystems translates into increasing the ground received signal-to-noise ratios. Therefore, low noise amplification with cooling operation is required. How- ever, the system designer must select an appropriate feedhorn antenna with low sidelobes and an adapted illumination at the edge of the reflector since the noise originated from the

This Impact Report identifies and summarises the diverse impacts, resulting from the £500m of UK funding of Science and Technology in 2013, using numerous quantitative metrics and short case study extracts.  It shows how the varied impacts of a national science and technology organization and its many funded programmes can be annually identified, captured, tracked, and summarised in a public document.

The report was produced for, and by, the Science and Technology Facilities Council (STFC) -  the UK Research Council responsible for funding: (1) all UK astronomy, particle and nuclear physics research, (2) related UK science and technology facilities (e.g. as Harwell and Daresbury), (3) the UK contribution to international science (e.g. CERN, international telescopes and space missions), (4) innovation and business spin-off programmes, and (5) UK public engagement activities.

The Report was co-researched and co-authored by the STFC Impact Team, including myself while Impact Evaluation Manager in 2013, with Dr. Claire Dougan-McCallie (lead author/Head of Impact) and Jenny Beard, with additional input from senior managers, and many data and case study contributions from other key managers across STFC.

Varied key impacts are identified and reported including:

• Research amongst the best (by citation impact) in astronomy, nuclear and particle physics.
• Supported research of 226 Principal Investigators in 70 universities, led to 1,100 peer-reviewed papers in 2012.
• Facilities (the Diamond Light Source, ISIS and CLF) were used in 2012/13 by over 4,200 unique users , in over 2,400 experiments, producing over 1,000 papers in peer-reviewed journals.

• Technology from CERN benefited the UK economy by over £100 billion every year.
• Funding the development of the UK’s space, internet and computer animation industries, returned over £500 billion to the UK economy per annum.
• Funded Innovation Campuses hosted over 230 enterprises and supported over 5,000 jobs.
• UK industry won £43 million in contracts from the international subscriptions funded, and had accumulated a total of £150 million since 2005.

• Funded research inspired future generations to study STEM subjects, attracting 90% of UK undergraduates to study physics, funded 782 PhD students  and 16,800 student training days.
• Between 2009 to 2012 public engagement programmes engaged people on 58 million occasions, with 2 million people engaged in face-to-face activities in 2013 alone.

Abstract
- The rate 1.0725 is found frequently between many solar planets orbital and internal distances (a constant rate)
- I suggest this rate is found because of Lorentz Contraction Phenomenon
i.e.
- There's a difference in velocities = "light velocity" between 2 motions in the solar group (even if we can't measure or notice this velocities difference)
i.e.
There's More Than One Frame In The Solar Group

This paper suggests a clear argument as following:
1. The solar group is created by light beams, but we see these light beams in different forms (as matters and distances)

2. We see the light as matter (Specifically, bright fringes produced by light coherence we see as matters, where dark fringes we see as distances)

3. We see bright fringes as matters because our mind works by light velocity (Mind Thinking Process), so the whole matter around us is found because of the human mind effect.

4. to enable us to see the sun rays, Earth has to move with light velocity relative to the sun, to create a difference in velocities = c velocity

5. So, the sun creation depends on the difference in Earth and Sun motions = c velocity.

6. That's why Lorentz contraction phenomenon is seen in the solar orbital and internal distances, specifically with the constant rate = 1.0725, (which equals 7.25%), where the sun obliquity to ecliptic (7.25 degrees).

7. means, the sun creation process contains Lorentz Phenomenon Effect on the solar orbital and internal distances (and on many other values) 
8. The Distance can be defined as "A Form Of Energy", which is proved by the moon orbit regression yearly 19 degrees (Metonic Cycle) (otherwise how distance can move?) (that supports the claim that, distances are dark fringes produced by light coherence)

This Paper Consists Of 2 Parts
1st Part    : Theory Of Matter Creation
2nd Part    : Application on the theory (the solar group creation from the light) 
 Starting From The Solar Group First Energy
 Explaining The Energy Coherence (light coherence)
 Discovering The Matter Creation
 Providing The Solar Group Motions Harmony Reasons

[Abstract is written mainly for fellow-scientists/researchers; Summary is more 'broad'.] In September 1859, the famous "Carrington Event" occurred (with estimated Dst readings of −850 nT to −900 nT), the largest recorded solar geomagnetic event since accurate records were made, causing widespread failures to contemporary telegraph systems and producing brilliant polar aurorae. In July 2012, a solar storm of much greater strength almost hit earth, narrowly missing because we'd moved about nine (9) days [about 2.46% of earth's 365¼−day orbit] from its trajectory[70], with a peak Dst value of −1,182 nT, as reported by Space Weather[31]. As a result, astronomers & scientists worldwide began calculating the probability estimation of another catastrophic Carrington−like geomagnetic event, since current technology (communications, GPS, power grids, satellites, etc.) are much more vulnerable to a severe solar storms than in the past when the only 'electronics' available were long−wire telegraphs-before even the telephone had been invented. Prior published research gave widely varying probability estimations of another such event. Moreover, prior research did not take into account the upcoming Maunder Minimum or acceleration in the geomagnetic pole movement, and the acceleration in the collapse of earth's protective magnetic field; nor, did they account for "lesser" magnetic storms which were very destructive, in their own right, causing many failures of communications and the power grid in various parts of the world. Historically, earth's magnetic north pole has wandered at a rate of about 0-15 km/year, but beginning in 1990, it accelerated to its current velocity of about 60 km/year[64] [65][66], which affects compasses, GPS, & other navigation. Moreover, the last time earth's protective magnetic field dropped by 30%, it needed fully 3,000 years[56], but, at the rapid rate it's decreasing now, it's projected to need only about 338.5 or 363.2 years (or 364.3 years or 333.9583 years), to drop by another 30%, depending of which set of data is used. While the data aren't in complete agreement, they're all very close, and suggest that a "geomagnetic flip," with concurrent field collapse to almost zero strength, is imminent. This is relevant because the weaker earth's protective magnetic field gets, the less it protects earth from severe geomagnetic storms. We review solar/geomagnetic data of all storms from the Carrington Event until present and estimate the probability of another similar catastrophic solar storm in the next decade: Prior prominent research of another Carrington Event are, at one extreme, Riley's estimates of about 12% probability[50], and Moriña's estimates[40] about 1.17% (taking the average of "0.46% and 1.88%," from his research paper). We find an 8.57% chance of another Carrington−class solar storm in the next decade. While we may overestimate the probabilities of another similar storm, the dangers posed to modern−day technology (much more vulnerable to geomagnetic solar storms or EMP detonations) suggest that it's better to use cautious & conservative estimates-especially given new unknowns and variables, such as the impending geomagnetic flip and concomitant collapse of earth's protective magnetic field-which, of course, make us even more vulnerable to a "direct hit." I stand by my estimate as it's methods are sound, with results between both extremes in the reported literature-and put forth proposed solutions for lawmakers and citizens.

The Hypothesis

                                  "There's No Gravity Found By The Sun"

This paper provides 5 proves for this hypothesis which are:
1- Planet Orbital Distance disproves The Sun Gravity Concept
2- The Sun Gravity Value disproves The Sun Gravity Concept
3- The Planet Velocity disproves The Sun Gravity Concept
4- The moon orbit analysis proves the solar group current description is incorrect.
5- The Solar Group is One Machine consists of all solar planets.

Black holes have turned out to be the cornerstone of both physics and popular belief. But what if we were to realize that exact black holes cannot exist, even though their existence is apparently suggested by exact general relativistic solutions, and Roger Penrose won the 2020 Nobel Prize in Physics ‘for the discovery that black hole formation is a robust prediction of the general theory of relativity’? While it might seem far-fetched to claim so, it will be worth remembering that the finest theoretical physicists like Albert Einstein and Paul Dirac did not believe in black holes, and Stephen Hawking finally thought that there are no exact black holes.
While the black hole paradigm has become commonplace in popular consciousness, in the last decade, noise has consistently grown about the many physical effects which can inhibit the formation of exact mathematical black holes. In The Rise and Fall of the Black Hole Paradigm, Abhas Mitra shows us how, much before these developments, he had proven why the so-called black holes must only be black hole pretenders. He identified these black hole candidates to be Magnetospheric Eternally Collapsing Objects (MECOs), and along with Darryl J. Leiter and Stanley L. Robertson, generalized them. Recent evidence for the existence of strong magnetic fields around so-called black holes may provide confirmations of his claim.

A claim against Nobel Prize Board Decision – in Physics -2018 
Best Greetings
I send this paper as a claim to the Nobel Prize Decision Board - for their decision - for Nobel Prize in physics  2018

Of course I have nothing against the great people who receive the Nobel Prize in Physics 2018 and I congratulate them for their great works

But at my side, I found there's a serious question here

Because I explained frequently in my research that, there's a serious contradiction in physics current theories and we can't understand the solar group geometry if no one solves this contradiction…

I Provided many hard arguments to prove this claim and thought that, the Nobel Prize Board will support me to solve this contradiction in physics.
But I found the Board decision avoids my work!
For that reason I summarized the main idea in this paper and send it as a claim to the Nobel Prize Decision Board   
And I wish the board will accept to give me a chance to explain and defend my point of view..
With the Best Regards

Gerges Francis Tawdrous
TEL +201022532292
E-mail georgytawdrous@yandex.ru
Linkedln https://eg.linkedin.com/in/gerges-francis-86a351a1
Facebook https://www.facebook.com/gergis.tawadrous
Academia https://rudn.academia.edu/GergesTawadrous

All my papers
http://vixra.org/author/gerges_francis_tawdrous

- Earth Moon Motion proves "The Train Motion Concept"
- "The Train Motion Concept" states that the solar planets move together as train carriages – i.e. – there's no solar planet moves individually or independently from others –instead –all solar planets move together (as train moves with its carriages together)- this concept is explained in 2nd hypothesis of my research. 

- Earth & Moon Motions show their cooperation with Saturn one.


- Earth, Moon and Saturn Motions show a deep cooperation between 3 planets – which produce the following data:
Harmony Data
1. Earth daily moves a distance =2.58 mkm = 0.985 degrees to complete 360 degrees in 365.25 days… i.e. Earth during 29.53 days move  29.2 degrees
And
2. The moon moves daily 2.58 mkm but the moon during the day moves 13.18 degrees to perform 360 degrees during 27.3 days
Means
- The moon during 29.53 days move a distance = 389.2 degrees
389.2 degrees – 360 degrees = 29.2 degrees  ….Why these values equal?
I- More Data
Metonic Cycle Period 6939.75 days = 19 x 365.25 days (Sidereal Days)
= 235 x 29.53 days (Lunar Synodic Month)
= 20 x 346.6 days (Nodal Year)

Saros Cycle Period 6585.321 days = 241 x 27.32 days (Lunar Sidereal Month)
= 19 x 346.6 days (Nodal Year)
= 223 x 29.53 days (Lunar Synodic Month)
The harmony in degrees are seen in the cycles harmony
This harmony proves (1) The Train Motion Concept (2) Earth & Saturn cooperation

The Square Kilometre Array (SKA) will be the largest radio telescope ever built, aiming to provide collecting area larger than 1 km 2. The SKA will have two independent instruments, SKA-LOW comprising of dipoles organized as aperture arrays in Australia and SKA-MID comprising of dishes in South Africa. Currently the phase-1 of SKA, referred to as SKA1, is in its late design stage and construction is expected to start in 2020. Both SKA1-LOW (frequency range of 50-350 MHz) and SKA1-MID Bands 1, 2, and 5 (frequency ranges of 350-1050, 950-1760, and 4600-15300 MHz, respectively) are important for solar observations. In this paper we present SKA's unique capabilities in terms of spatial, spectral, and temporal resolution, as well as sensitivity and show that they have the potential to provide major new insights in solar physics topics of capital importance including (i) the structure and evolution of the solar corona, (ii) coronal heating, (iii) solar flare dynamics including particle acceleration and transport, (iv) the dynamics and structure of coronal mass ejections, and (v) the solar aspects of space weather. Observations of the Sun jointly with the new generation of ground-based and space-borne instruments promise unprecedented discoveries.

We still try to understand the data…
(1)
Mercury Day Period      = 2 Mercury Orbital Periods =3 Mercury rotation periods
(2)
Uranus Orbital Distance  = 2 Saturn Orbital Distances
(3)
Also I have claimed that
Moon Daily Displacement 88000 km is used As 2 x 88000 km
Shortly
Why The Rate 2: 1 Is Found In The Solar System Geometry? 

Paper Hypothesis
Mercury Periods Data causes The Moon Daily Displacement 88000 km to be used in  double value = 2 x 88000 km
The Moon Daily Displacement (88000 km) effects On Mercury Periods Data

Spirit, Power and Axis of everything, in our mortal eyes there is Emptiness: for the truly complete in these empty ones is empty. The Moon, the Axis of everything in our world, is therefore empty for them, and SHOULD BE empty. // Дух, Сила и Ось всего, в смертных очах — Пустота: ибо истинно полное в них, пустых, пусто. Луна, Ось всего в нашем мире, для них посему и пуста, и ДОЛЖНА БЫТЬ пустой.

Let's summarize the contradiction point in following:
(1)
Lorentz Transformations tell us that – Particle 4 values are changing with high- velocity motion – these values are: Particle Mass, Length, Distance And Time
In our previous discussion- we have concluded that – we have to accept the particle length contraction and mass increasing as real phenomena which can't be illusion of measurements – we have reach to this conclusion based on 2 reasons – (1st) because of the empirical proves for these features (length contraction- mass increasing)- where we need to protect the physical experimental measurements credibility  and (2nd) Because we don't want to make ourselves as The Universe Reference Point.
Shortly
Lorentz Transformations tell that Particle Mass, Length, Distance And Time are changed by the same reason – i.e. they are dealt as similar to each other
(2)
The special theory of relativity is built on Lorentz Transformations
But
In The General Theory of relativity Einstein tells us
"The existence of gravitational field is inseparably bound up with the existence of Space. On the other hand a part of Space may very well be imagined without electromagnetic field," …
……..Since according to our present conceptions the elementary particles matter are also, in their essence, nothing else than condensations of the electromagnetic field….
Namely gravitational ether and electromagnetic field or – as they might also be called – Space And Matter   

The Contradiction Point
Lorentz Transformations deal with Space and Matter as equal ….But
The General theory of relativity distinguishes between the space and matter 

Gerges Francis Tawdrous +201022532292

There's A Light Beam Travels With 1.16 Million Km/Sec
This paper tries to prove this fact

References
My Research Basic Arguments (Part I)
My Research Basic Arguments (Part II)
My Research Basic Arguments (Part III)

Gerges Francis Tawdrous +201022532292

Gravitational microlensing has revealed an extensive population of “nomadic” planets not orbiting any star, with Jupiter-mass nomads being more populous than main sequence stars. Except for distant objects discovered through microlensing, and hot, young nomads found near star formation regions, to date only a small number of nomad candidates have been discovered. Here I show that there should be significant numbers of mature nomadic exoplanets close enough to be discovered with existing or planned astronomical resources, including possibly dozens of massive planets closer than the nearest star. Observational data are used to derive models relating mass, radius, heat flux and magnetic dipole moment; these are used to show the observability of nomads in the IR, due to thermal emissions, and at radio frequencies, due to cyclotron maser instabilities. These neighboring nomadic planets will provide a new exoplanet population for astronomical research and, eventually, direct exploration by spacecraft.

The fields of solar radiophysics and solar system radio physics, or radio heliophysics, will benefit immensely from an instrument with the capabilities projected for SKA. Potential applications include interplanetary scintillation (IPS), radio-burst tracking, and solar spectral radio imaging with a superior sensitivity. These will provide breakthrough new insights and results in topics of fundamental importance, such as the physics of impulsive energy releases, magnetohydrodynamic oscillations and turbulence, the dynamics of post-eruptive processes, energetic particle acceleration , the structure of the solar wind and the development and evolution of solar wind transients at distances up to and beyond the orbit of the Earth. The combination of the high spectral, time and spatial resolution and the unprecedented sensitivity of the SKA will radically advance our understanding of basic physical processes operating in solar and heliospheric plasmas and provide a solid foundation for the forecasting of space weather events. Advancing Astrophysics with the Square Kilometre Array

Abstract
I claim that Mars immigrated from his original Point at orbital distance =84 mkm to dwell in his point at orbital distance 227.9 mkm..
And this immigration causes the following results:
1- A disturbance for the planet diameter and orbital distance relationship (which is proven clearly from the solar planets order) 
2- Pluto Immigration, because Pluto had to move to the Solar group End where he before belonged to the inner planets.
This study tries to prove these facts
Also I provide in this Study my suggested description for the solar group. 


The solar planets order tells us clearly that there's a relationship between the planet diameter and his orbital distance… this conclusion we get easily from the following planets order:
Mercury – Venus – Earth..
The previous planets order tells us a clear rule "Planet Greater Diameter has A Greater Orbital Distance"     
Something was happened with Mars
After Mars this rule is reversed as we see in the following planets:
Jupiter – Saturn - Uranus – Neptune – Pluto
The rule became "Planet Greater Diameter has A Shorter Orbital Distance"     
(Please Note/ Uranus greater in diameter and less in Mass from Neptune that tells us the planets order depends on their diameters and NOT on their Masses)
What happened with Mars?
Mars immigration from his original point in 84 mkm to his new point in 227.9 mkm
Let's return Mars to his original point at orbital distance = 84 mkm 
What the solar planets order will be:
Mercury – Mars - Venus – Earth..
This follows completely the rule "Planet Greater Diameter has A Greater Orbital Distance"     
Based on this description there are 2 planets at least immigrated from their original points:
1- Mars immigrated from his original point in 84 mkm to his new point in 227.9 mkm
2- Pluto who belonged before to the solar inner planets (my hypothesis) and had to move to the End of the solar group because the rule became reversed…
This paper tries to prove these facts
To do that we have to prove the following:
1- Mars moved from his original point (Mars is exceptional Planet)
2- Pluto belonged before to the solar inner planets..

This paper contains 2 points
3- Mars Original orbital distance was 84 mkm
4- An Alternative Solar Group Description

Site location study in a particular type of observatory must be considered in order to come up with desired data. This should take in to account specifically when doing radio astronomy. In the Philippines, radio astronomy has limited access to research since there is no constructed observatory for this kind of discipline. Through this study, it can give various choices in selecting locations in constructing radio astronomy observatory. For this to materialize, the researcher identified the parameters that affects the performance of radio observation such as: (1) population density, (2) climate type, (3) road network, and lastly (4) contour shielding. Each of these factors have shown direct correlation with the Radio Frequency Interference (RFI) based from the initial analysis through Multi Criterion Decision Analysis (MCDA). The researcher was able to rank 16 regions in the Philippines in which we can deploy the best radio astronomy observatory site.

Орел и решка Человека.
______________

Имя «зеленые человечки», носимое Пришельцами, оправданно: кожа их впрямь зелена, и цвет этот, писал Циолковский, дань пище их: как солнцем лист, они кормятся чистым Огнем и с тем есть автотрофы. Цвет серый Гостей, им второй — автотрофия та же: цвет куколки, в метаморфозе живимой не внешнею пищей, а Духом, Огнем Изнутри.

Best regards
When I have discovered that..
Saturn Orbital Distance = Saturn Uranus Distance
I have asked Why? But the usual answer was ……
It's Pure coincidence….!

Later I have discovered more equalities….As the following: 
 
1. Saturn Orbital Distance = Mars Orbital Circumference = Pluto Eccentricity distance = Saturn Uranus Distance = 1433.5 million km

2. Mercury Saturn Distance = Neptune Pluto Distance = 1375 million km

3. Saturn Pluto Distance = Mercury Neptune Distance = 4436.5 million km

Then I have asked again… why These Distances Are Equal? Is there a geometrical reason behind?…but the usual answer always be …. " Pure Coincidences" 

The question wasn't so simple and the answer was mentioned…. I ask clearly… are the solar planets members in the same body? or parts in the same building?- shortly are the solar group as the human hand and the fingers are similar to the planets? means the planets are created and moving depending on each other because all of them consist one machine –one body –one building – one geometrical structure – means the planets aren't separated from each other– but connected with each other.
(that means the space between the planets is a method to connect each planet with others and not to separate each planet from the others)…. This is my question aim!
And the current theory understood that clearly…
And told also a clear answer … that
Any solar planet is separated from the others - each planet is found and move independently..
So the two visions are clear before our eyes ……And the fighting is clear also….

The Solar Group Classical Vision: tells us that… the planet is created independently and move by gravity with the sun without effect of the other solar planets….

My Suggested Vision Is:
The Solar Group is one body – one machine – one building – one geometrical structure – No Planet can be found or move independently from the other planets …. Even the sun herself can't be found without the solar planets… we deal here with one machine – one geometrical structure- so if this geometrical structure has many elements we should be wise enough to see that these elements are members in the same geometrical structure and this structure is found by the cooperation and integration of his members…..
We should fight to prove that we are correct and the current theory is mistaken… Please read the argument…

Mark Buchanan’s recent Thesis column — ‘Searching for trouble?’ — accurately summarizes key objections to Messaging Extra-terrestrial Intelligence (METI), in which powerful, intentional signals are transmitted to specific astronomical targets, in the hope of a reply. Most notably, Buchanan characterizes METI as seeming “inherently risky”.

The risk we most often hear about — alien invasion — is simply not plausible, however. Any civilization slightly more advanced than we are could already detect our presence through our accidental electromagnetic radiation. Only a virtual twin of modern terrestrial technology would pick up information-rich beacons but be blind to the BBC at interstellar distances. If we are in danger of an alien invasion, it’s too late.

This second part contains these chapters, in two files:

1 Chemistry: Reading Spectrograms
2 Performance Art: Problems of Documentation
3 Field Geology: Deductions from Beach Stones
4 Economics: Sirens in Classics, in Philosophy, and in Economic Theory
5 Linguistics: Medieval Irish Color Terms
6 Astrophysics: Doppler Tomography of Accretion Disks
7 Law: Video-game Technology in the Irish Bloody Sunday Tribunal
8 Computer Science: Visualizing the Internet
9 Occupational Therapy: Exercises in Doing, Being, and Becoming
10 Speech and Hearing Science: Speech Spectrograms
11 Restorative Dentistry: Matching Colours in Porcelain Crowns
12 Radio Astronomy: Observations of the Galactic Center
13 Archaeology: Imaging and Mapping Practices
14 Mapping: Uses of Geological Maps
15 Art History: Iconographic Analysis
16 Civil Engineering: A High Resolution Aerial Photograph

Originally published as Visual Practices Across the University, with contributions by thirty-five scholars (Munich: Wilhelm Fink Verlag, 2007).

In order to meet the requirements of the new generation of radio telescopes, we have developed a new topology called DYQSA, which stands for DYson Quad-Spiral Array. The design exhibits dual circular polarization in contrast to dual linear polarization of state-of-the-art feeds. It covers the required ultra-wideband (UWB) from 2 GHz to 14 GHz with an almost constant and real input impedance which facilitates the design of the feeding structure and the Low Noise Amplifiers (LNAs). Different versions are investigated for enhancing feed performance, ensuring higher aperture efficiencies and mechanical stability. Simulation results of the reflector loaded by the proposed feed show an aperture efficiency of 65 ± 5% can be achieved with a noise antenna temperature around 14 K and a System Equivalent Flux Density (SEFD) of about 1300 Jy, both averaged over the required bandwidth at zenith. Measurements of the single-element and the four-element feeds are presented. Comparisons with other state-of-the-art feeds are shown in terms of total aperture efficiencies, design adaptability to different reflectors, calibration signal injection, the required number of LNAs per feed, cost, and physical volume.

With increasing levels of electromagnetic interference (EMI) in suburban areas and high-tech campus environments, it is increasingly necessary to relocate radio telescope receiving equipment to remote areas. For researchers with limited budgets as well as the amateur radio astronomer, the costs associated with remote control of equipment can be extreme.  This paper discusses low-cost but reliable approaches to remote control. Presented at the SARA Western Conference, March 2016 and published in Proceedings.