Tag: Pulse Compression

An illustration of bandwidth-delay product
Radar and Localization / Wireless and SDR

An Intuitive View of Time-Bandwidth Product (TBP)

Time-Bandwidth Product (TBP) of a waveform is a foundational term frequently used in communications and radar community. However, I have never seen any book or online resource explain the core idea in an intuitive manner. Even though I understood the concepts of degrees of freedom and packing of resources in an $N$-dimensional space, I found it hard to come up with a visualization of time-bandwidth product in my head. This is what I set out to accomplish in this article. Let us start with the term Bandwidth-Delay Product (BDP), a term frequently used in communication networks. We will shortly relate

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Orange vs tangerine
DSP

The Fourier Doppelgangers

It is well known that Fourier Transform is unique under certain conditions that are satisfied by almost all practical signals. Then, how can we resolve the following contradiction? Consider a sinc pulse and Linear Frequency Modulated (LFM) pulse (a chirp) in time domain. The sinc pulse is defined as \[ \text{sinc}(t) = \frac{sin(\pi t)}{\pi t} \] Now the spectrum of a sinc pulse in time in an ideal case is a rectangular signal in frequency domain, which is the most fundamental relation in signal processing. Both the sinc pulse and its spectrum are plotted in the left half of the

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Low pulse width and higher resolution
DSP / Wireless and SDR

The Power of Pulse Compression

Human eyes can only see in the visible part of the electromagnetic spectrum. Radar (Radio Detection and Ranging) is a device that extends our ability to detect the environment far beyond what is allowed by the visual nervous system, see the article on Frequency Modulated Continuous-Wave (FMCW) radars. Today we talk about the idea of pulse compression and the role it plays in target detection. As opposed to a Continuous-Wave (CW) radar, a pulsed radar transmits a short burst of energy followed by a period of silence during which it listens for the echo received from the target. As shown

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