FIG. 5A is a block diagram of an illustrative embodiment of an interrogator device 500 that may be used as part of process 1600 (e.g., to perform acts 1602 and 1608 of process 1600). Interrogator device 500 is not limited to being used as part of process 1600 and may be used in any other suitable way, including as part of any other process described herein, as aspects of the technology described herein are not limited in this respect.
As shown in FIG. 5A, interrogator 500 comprises a substrate 505 having a differential feed circular polarized transmit antenna 502 and a differential feed circular polarized receive antenna 506 disposed thereon. The interrogator 500 further comprises semiconductor die 504 having transmit and receive circuitry integrated thereon. The transmit and receive circuitry integrated with the semiconductor die 504 is differentially coupled to antenna 502 via lines 507a and 507b. The transmit and receive circuitry on the semiconductor die is also differentially coupled to antenna 506 via lines 508a and 508b.
