Bistatic radar and passive radar systems are emerging as powerful tools for detecting and characterizing space objects, offering flexible and cost-effective alternatives to traditional monostatic radar architectures. Unlike conventional systems where the transmitter and receiver are co-located, bistatic radar separates these components, while passive radar is a bistatic radar which relies on non-cooperative transmitters such as commercial broadcast or communication signals. This tutorial introduces the fundamental phenomenology underlying how electromagnetic waves interact with satellites, debris, and other orbital targets in these configurations. Key topics include scattering behavior, radar cross-section variability, orbital geometry effects, and the influence of signal wavelength and polarization. Understanding these principles is essential for interpreting detection signatures and optimizing system performance in increasingly congested orbital environments.

Building on this foundation, the tutorial explores practical techniques used to detect and track space objects using bistatic and passive radar. We will examine signal processing methods such as cross-correlation, Doppler analysis, and time-delay estimation, along with strategies for mitigating noise and interference in real-world scenarios. The session also highlights system design considerations, including transmitter-receiver geometry, waveform selection, and sensor network integration. Case studies and examples will illustrate how these methods are applied in space domain awareness (SDA), particularly for tracking small debris and objects in low Earth orbit. By the end of the session, attendees will gain a clear understanding of both the theoretical and operational aspects of these radar approaches, equipping them with the knowledge to evaluate and implement advanced detection techniques.

The tutorial will cover a comprehensive set of concepts that underpin bistatic and passive radar detection of space objects, beginning with the geometric and physical differences between monostatic, bistatic, and multistatic configurations. Participants will explore the phenomenology of electromagnetic scattering from satellites and debris, including how radar cross section varies with aspect angle, material properties, and signal frequency. The session will introduce key measurement domains, such as range, Doppler, and angle, and explain how these are extracted in non-cooperative sensing environments where the transmitter is separated or unknown. Core signal processing techniques such as matched filtering, cross-ambiguity functions, time-delay estimation, and Doppler shift analysis will be discussed in the context of detecting weak targets against clutter and interference. The tutorial will also address the role of illuminators of opportunity, such as FM radio, digital TV, and satellite communications, and how their waveform characteristics influence detection performance. Additional topics include synchronization challenges, calibration strategies, and the impact of orbital dynamics on observation geometry and revisit rates. Finally, the session will touch on data association and tracking methods, highlighting how measurements from distributed sensors can be fused to support space situational awareness and improve the detection of small or otherwise difficult-to-observe objects.

After attending the tutorial session, the participants will be able to: