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\secc Sensitivity and noise number
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\secc Sensitivity and noise number
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Sensitivity and noise number are parameters that are tied together, but multi antenna and multi-receiver arrays force the price of receiver to be kept at minimal value. This implies that the sensitivity and noise number have to be at least so good in the detection (signal $/$ noise $>$ 1 ) of an observed object, that it would be detected on the majority of receivers connected to an observation network.
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Sensitivity and noise number are parameters that are tied together, but multi antenna and multi-receiver arrays force the price of receiver to be kept at minimal value. This implies that the sensitivity and noise number have to be at least so good in the detection (signal $/$ noise $>$ 1 ) of an observed object, that it would be detected on the majority of receivers connected to an observation network.
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\secc Dynamic range
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\secc Dynamic range
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\label[dynamic-range-theory]
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\label[dynamic-range-theory]
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Dynamic range represents a huge problem of current radioastronomical receivers. This parameter is enforced by everywhere present humans made EMI radiation on RF frequencies. The modern radio astronomy receiver must not be saturated by this high levels of signals but still needs to have enough sensitivity to see faint signals from natural sources. Dynamic range is limited either by the construction of analogue circuitry in receiver or by the digitalisation unit.
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Dynamic range represents a huge problem of current radioastronomical receivers. This parameter is enforced by everywhere present humans made EMI radiation on RF frequencies. The modern radio astronomy receiver must not be saturated by this high levels of signals but still needs to have enough sensitivity to see faint signals from natural sources. Dynamic range is limited either by the construction of analogue circuitry in receiver or by the digitalisation unit.
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The maximal theoretical dynamic range of ADC could be estimated from ADC bit depth using a following formula \ref[dynamic-range]
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The maximal theoretical dynamic range of ADC could be estimated from ADC bit depth using a following formula \ref[dynamic-range]
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\label[dynamic-range]
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\label[dynamic-range]
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$$
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$$D.R. [dB] = 20 \cdot \log(2^n) $$
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D.R. [dB] = 20 \cdot \log(2^n) \eqmark
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$$
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The formula \ref[dynamic-range] gives values shown in table below \ref[ADC-dynamic-range].
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The formula \ref[dynamic-range] gives values shown in table below \ref[ADC-dynamic-range].
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\midinsert \clabel[ADC-dynamic-range]{Dynamic range versus bit depth}
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\midinsert \clabel[ADC-dynamic-range]{Dynamic range versus bit depth}
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\ctable{cc}{
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\ctable{cc}{
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