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From radioastronomer point of view its important radioastronomy has interest in primarily natural signals from surrounding universe. Radio astronomy do not have interest in terrestrial civilisation made signals. 

From a radioastronomer's point of view it is important that radioastronomy focuses its interest primarily on natural signals originating in the surrounding universe. It does not pay attention to the man-made signals created by our civilisation. 

Radioastronomy has a big problem at now. It is because  many terrestrial transmitters are active at this moment. All terrestrial  transceivers made dense signal mixture which can cause troubles not only to radioastronomers. 

However, it is due to these signals, that the current radioastronomy faces a disturbing problem. The problem arises from the fact, that there are many terrestrial transmitters active at the moment and all of them are sources of a dense signal mixture which can cause trouble not only to radioastronomers. 

RadioJOVE project brings opportunity for creating publicly available cheap radioastronomy receiver. But they used an old fashioned construction model which can work in desert, but it simply cannot work in modern civilisation as it is know in Europe.

As a consequence, there already exists attempts to control radiofrequency spectrum. As result of attempts to control the radiofrequency spectrum, the frequency allocation table was created. \fnote{\url{http://www.ukaranet.org.uk/basics/frequency_allocation.htm}} Radio-frequency allocation table table contains special bands allocated to radioastronomy use. However, for many reasons these bands are not clean enough to be used directly in radioastronomy observations. As a result, we cannot work in the same way as had the radioastronomers in the very beginnings of radioastronomy.  Many experiments, namely Cosmic microwave background detection and pulsar detection, cannot be nowdays realised in their original forms with satisfactory results. 

There are not other ways that searching for new methods for radioastronomy observations. New methods which allows us to work without completely clear radiofrequency bands and which allow us to see surrounding universe trough man made radiofrequency interference mixture.  One solution is use of already known natural radio frequency signals parameters. Natural signals usually have different signal properties from local interference. Natural object do not have a problem with transmitting in  bandwidth of tens megahertz in sub 100 MHz bands. This object are usually far away and the same signal could be received at almost half of Earth without any significant differences.  But it is also clear that signal parameters have drawbacks in reception power. The reception power of radioastronomy object is 1e9 smaller than signal power received from typical broadband radio transmitter.

The source of its dysfunction is a presence of strong radiofrequency interferences. These interferences are orders of magnitude stronger than Jupiter decametric emissions, whose detection was the main aim of the RadioJOVE project.

From above mentioned facts about natural radio signals is clear one result. Modern requirements on radioastronomy receiver are complete different from requirements in history. Radioastronomy is not limited by access to electronic components today, but it is limited by presence of electronic everywhere.   

From the above mentioned facts concerning the natural radio signals we can conclude that modern requirements imposed on a radioastronomy receiver are completely different from the requirements existing back in the history. Radioastronomy is no longer limited by an access to electronic components, today it is rather limited by the everywhere presence of electronic.   

In beginning of radioastronomy receivers were constructed as simple station with single antenna or multi antenna array with fixed phasing. This approach were used due to limits of previous electronics components and technology. Main challenges were noise number and sensitivity due to poor characteristic of active electronic components such transistors and vacuum tubes. 

In the beginning of radioastronomy, the receivers were constructed as simple stations with single antenna or multi antenna array with fixed phasing. This approach was used because of the existing limits of electronic components and technologies. Main challenges of those times were the problem of noise number and low sensitivity, both present due to the poor characteristics of active electronic components such as transistors and vacuum tubes. 

Most of today operational radioastronomy equipments were constructed in this manner. They were constructed usually shortly after WWII or during The Cold War as parts of military technology.  

Most of the present-day operational radioastronomy equipments were constructed in similar manner. They were produced usually shortly after the WWII or during The Cold War as a part of military technology.  

But today we have access to components with quality, repeatability and price is completely district from components accessible for previous generation of radioastronomers.  Then we could develop better radioastronomy equipment which will be powerful enough for make new astronomy discovery.\fnote{Most of astronomy related discoveries in last fifty years came from radioastronomy.} 

Today we have an access to components having quality, repeatability and price completely different from the components accessible by previous generation of radioastronomers.  That is why we can develop better radioastronomical equipment, powerful enough to make it new astronomical discoveries possible.\fnote{Most of astronomy-related discoveries in the last fifty years came from radioastronomy.} 

Today radioastronomy knows several observation types.

Current radioastronomy knows several types of observations.

All of these observations ideally needs high frequency resolution and stability. Wide observation bandwidth in hundreds of MHz is usually desirable for easier differentiation of source types. 

All of theme ideally needs high frequency resolution and stability. Wide observation bandwidth in hundreds of MHz is usually desirable for easier differentiation of source types.