Bistatic Observations With SuperDARN HF Radars: First Results. Issue 8 (7th August 2020)

• Record Type: Journal Article
• Authors: Shepherd, S. G.; Sterne, K. T.; Thomas, E. G.; Ruohoniemi, J. M.; Baker, J. B. H.; Parris, R. T.; Pedersen, T. R.; Holmes, J. M.
• Is Part Of: Radio science. Volume 55:Issue 8(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-08-07
• Subjects: SuperDARN -- bistatic -- IRI -- ray tracing -- radar -- scatter; Radio meteorology -- Periodicals; Radio wave propagation -- Periodicals; 621.38405
• DOI: 10.1029/2020RS007121
• Languages: English
• ISSNs: 0048-6604

Abstract

Abstract: Super Dual Auroral Radar Network (SuperDARN) radars operate in a coordinated but monostatic configuration whereby high‐frequency (HF) signals scattered from ionospheric density irregularities or from the surface of the Earth return to the transmitting radar where Doppler parameters are then acquired. A bistatic arrangement has been developed for SuperDARN radars in which HF signals transmitted from one radar are received and analyzed by another radar that is separated by a large distance (>1, 000 km). This new capability was developed and tested on radars located in Oregon and Kansas. Numerous 3‐day bistatic campaigns have been conducted over a period extending from September 2019 through March 2020. During these campaigns three distinct bistatic propagation modes have been identified including a direct mode in which signals are transmitted and received through the radar side lobes. Direct mode signals propagate along the great‐circle arc connecting the two bistatic radar sites, reflecting from the ionosphere at both E region and F region altitudes. Two additional modes are observed in which HF signals transmitted from one radar scatter from either ionospheric density irregularities or from the surface of the Earth before propagating to the bistatic receiving radar. Ray tracing simulations performed for examples of each mode show good agreement with observations and confirm our understanding of these three bistatic propagation modes. Bistatic campaigns continue to be scheduled in order to improve technical aspects of this new capability, to further explore the physical processes involved in the propagation and scattering of HF bistatic signals and to expand the coverage of ionospheric effects that is possible with SuperDARN. Key Points: Bistatic capability has been developed and demonstrated using two midlatitude SuperDARN radars Three distinct propagation modes were commonly observed during bistatic campaigns Good agreement between observations and ray tracing using the IRI model is obtained