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We have an access today to components with much higher quality, repeatability and a lower price as compared to the components accessible to previous generation of radioastronomers. That is why we can develop a better radioastronomical equipment, powerful enough to make new astronomical discoveries possible.\fnote{Most of astronomy-related discoveries in the last fifty years came from radioastronomy.}
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We have an access today to components with much higher quality, repeatability and a lower price as compared to the components accessible to previous generation of radioastronomers. That is why we can develop a better radioastronomical equipment, powerful enough to make new astronomical discoveries possible.\fnote{Most of astronomy-related discoveries in the last fifty years came from radioastronomy.}
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We have the capacities necessary to develop a receiver which will have a wide bandwidth, a high third-order intercept point and preferably an option for phase and frequency locking to other receivers located at another radioastronomical site at the Earth. Currently there exist several receivers with the above-mentioned parameters, for example USRP2, USRP B210 \glos{USRP}{Universal Software Radio Peripheral} or HackRF, which are commercially available. However all of them lack scalability and have higher prices unaffordable to our amateur radioastronomy network. Scalability and redundancy that are the main requirements of noise reduction algorithms which motivated this diploma project.
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We have the capacities necessary to develop a receiver which will have a wide bandwidth, a high third-order intercept point and preferably an option for phase and frequency locking to other receivers located at another radioastronomical site at the Earth. Currently there exist several receivers with the above-mentioned parameters, for example USRP2, USRP B210 \glos{USRP}{Universal Software Radio Peripheral} or HackRF, which are commercially available. However all of them lack scalability and have higher prices unaffordable to our amateur radioastronomy network. Scalability and redundancy that are the main requirements of noise reduction algorithms which motivated this diploma project.
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New radio astronomy systems such LOFAR \glos{LOFAR}{Low-Frequency Array} are explicit examples of the scalability and redundancy approach. LOFAR has completely different and novel structure developed to solve the problems of radioastronomy signal reception. It exclusively uses multi antenna arrays and mathematical algorithms for signal handling. Radio signals recorded by LOFAR can be used in multiple ways: radio images can be computed (if sufficient cover of u/v plane is achieved), radiation intensity can be measured, spectrum can be analysed for velocity measurement, etc.
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New radio astronomy systems such LOFAR\glos{LOFAR}{Low-Frequency Array} are explicit examples of the scalability and redundancy approach. LOFAR has a completely different and novel structure developed to solve the problems of radioastronomy signal reception. It uses exclusively multiantenna arrays and mathematical algorithms for signal handling. Radio signals recorded by LOFAR can be used in multiple ways: radio images can be computed (if sufficient cover of $u/v$ plane is achieved), the radiation intensity can be measured, the spectrum can be analysed for velocity measurement, etc.
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\sec Required receiver parameters
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\sec Required receiver parameters
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The novel approach of receiver construction described above goes hand-in-hand with new requirements on receiver parameters as well. Currently no additional attempts to improve the signal-to-noise ratio on single antenna are performed. There are however other parameters requested nowadays.
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The novel approach of receiver construction described above goes hand-in-hand with new requirements on receiver parameters as well. Currently no additional attempts to improve the signal-to-noise ratio on single antenna are performed. There are however other parameters requested nowadays.
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