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What is software defined radio (SDR)?
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Software Defined Radio (SDR) utilises a radio frontend combined with a programmable processing unit, usually a CPU and/or FPGA. The processing unit handles many tasks that would conventionally be handled by analogue components, providing the flexibility to reconfigure the device to handle a multitude of protocols and waveforms via software modifications.
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What is a channelizer?
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A channelizer is an algorithm that selects a specified frequency band from a signal. It allows signals of interest to be extracted from a broader swathe of spectrum, allowing those signals to be analysed and/or stored. Channelization allows the amount of data analysed and stored to be significantly reduced, saving processing power and disk space.
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What is a multi-channel receiver?
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A multichannel receiver utilises multiple receiver inputs or digital techniques to handle multiple channels from a single receiver input. Modern multi-channel receivers tend to use software defined radio (SDR) architectures with fewer physical receiver inputs, since it allows greater flexibility, reduced cost-per-channel and more compact systems.
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What is monitoring bandwidth?
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Monitoring bandwidth, or instantaneous bandwidth, refers to the bandwidth of the RF spectrum that a receiver can digitise at any given time, without returning the local oscillator.
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What is the difference between digital downconverters (DDCs) and digital drop receivers (DDRs)?
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The terms DDC and DDR are used interchangeably. The term DDC is typically used as a general term, referring to the practice of downconverting a received (wideband) signal into baseband, discarding extraneous data, and keeping just the narrowband signal of interest. The term DDR is more often used in the context of electronic warfare and signals intelligence, referring to the number of narrowband channels a receiver system can monitor at any given time.