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Superheterodyne Receiver

98 bytes added, 19:47, 12 February 2016
/* What about SDR */
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It is sometimes mistakenly stated that Software Defined Radio is something different from the superheterodyne receiver design.  This is not true.  Today's SDRs still use superheterodyne.  This is due to the consistent performance a superheterodyne receiver offers across a large range of frequencies while maintaining good sensitivity and selectivity.It is sometimes mistakenly stated that Software Defined Radio is something different from the superheterodyne receiver design or does not require superheterodyning.  This is not true.  Today's SDRs still use superheterodyne.  This is due to the consistent performance a superheterodyne receiver offers across a large range of frequencies while maintaining good sensitivity and selectivity.Modern SDR receivers are using variations in traditional superheterodyne.  They do not "sample" the antenna directly.  Despite some appeal, the data converters are not directly on the antenna.  It is simply not practical to do it this way.  An analog front-end remains necessary before the ADC in the receive path and after the DAC in the transmit path that does the appropriate frequency translation, this is where superheterdyning is being used.Modern SDR receivers are using variations in traditional superheterodyne.  They do not "sample" the antenna directly.  Despite some appeal, the data converters are not directly on the antenna.  It is simply not practical to do it this way.  An analog front-end remains necessary before the ADC (Analog to Digital Converter) in the receive path and after the DAC (Digital to Analog Converter) in the transmit path that does the appropriate frequency translation, this is where superheterdyning is being used.
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