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Radio-frequency sensing and communication systems which use a waveform for more than one function offer the promise of improved spectral efficiency and streamlined hardware requirements. Control of orbital angular momentum (OAM) may be used to increase data-rates and improve radar sensitivity to certain chiral targets. This paper presents finite-difference time-domain simulations which model a gigahertz-frequency OAM radar capable of transmitting information via OAM-mode modulation. The unique chirality-detection capability of OAM radar is demonstrated, as well as simple information transmission. Simulation scope and radar specifications are designed with an eye toward developing a dual function ground penetrating radar (GPR) with OAM mode control.
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This content will become publicly available on January 5, 2026
Development of a Box for GPR Testing with Coarse Aggregates
Ground penetrating radar (GPR) is a nondestructive tool for investigating the subsurface. When used in laboratory testing, large boxes to contain the test specimen aggregate or soil are necessary. However, boxes created for GPR testing have some unique requirements such that they do not interfere with the sensitive GPR equipment. This paper presents the design and construction of economical boxes for GPR testing. Key design requirements for this test box were: minimal use of metal, compatible with a wide frequency range from 300 MHz to 1.6 GHz, capable of specimen saturation, capable of efficiently breaking down the specimen, and can be used for the preparation of hundreds of test specimens.. The literature does not contain many examples of test setups that would fulfill these objectives nor does it include specific instructions on how to create a box to achieve them. This paper presents the final economical design for laboratory testing of aggregate using GPR.
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- Award ID(s):
- 2301588
- PAR ID:
- 10596483
- Publisher / Repository:
- Transportation Research Board
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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