A Flexible Next Generation Incoherent Scatter Radar Architecture for HAARP Diagnostic Support and Enhanced Science Capabilities

Abstract:

Since the late 1950s, the technique of incoherent scatter radar (ISR) has proved to be a powerful and flexible ground-based approach for probing the dynamics of the Earth’s ionosphere. The use of Thomson scatter allows full altitude profiles of the ionospheric plasma parameter state. Incoherent scatter (IS) capable radars have the unique ability to directly sense altitude profiles of both electron and ion temperatures at < 1 eV energies, ion composition, ion velocities, and derived products including conductance and photoelectron information.

The very weak nature of IS requires an advanced radar with high power-aperture product. Early IS radar systems have heritage in DoD / ARPA efforts, with the modern AMISR system implemented by the National Science Foundation. Recent international efforts to develop the EISCAT 3D radar in northern Scandinavia are underway, but radar technology has already advanced greatly relative to that design.

A radar development effort to implement a more practical Geospace radar has been underway through AFRL and NSF sponsorship. The resulting Next Generation Incoherent Scatter Radar (NextISR) architecture is currently ready for scaling to a prototype aperture size. An associated MIT Incoherent scatter radar Performance Simulator (MIPS) design model enables accurate exploration of IS measurement capabilities for a wide range of radar configurations, locations, and Geospace conditions.

HAARP’s research program on the effects of ionospheric modification through absorption of high power HF waves would benefit from information on the full altitude-dependent ionospheric state and the ionospheric response to RF heating. The characterization of multiple excited plasma waves, instabilities, and the associated bright scattering features and propagation to non-heated regions is also of great interest.

NextISR systems use a locally bi-static architecture that produces a separation of TX and RX elements. The flexible nature of NextISR enables a Geospace radar network tailored to the HAARP facility, with crucial, site-optimized, IS radar diagnostics including multi-static ion line and plasma line vector measurements. We will give a NextISR overview, present notional radar architectures relevant to HAARP diagnostic needs, and compare predicted performance to existing radars.