Introduction <p>Rabi oscillation, a fundamental phenomenon in quantum mechanics, underpins the operation of high-sensitivity quantum magnetic field sensors. Concurrently, the proliferation of the Internet of Things (IoT) has driven a critical demand for miniaturized, versatile wireless sensor nodes, where magnetic field sensors are pivotal for applications ranging from geomagnetic navigation to biological monitoring. A significant design challenge in integrating such sensors into compact devices is the physical and electromagnetic conformity between the essential magnetic induction coil and the wireless transceiver antenna.</p> Purpose <p>This study aims to design and realize a novel magnetic field sensing device that resolves the conformity problem. The core objective is to enable a single physical coil structure to function simultaneously as both a high-efficiency magnetic induction sensor and an effective spiral antenna for wireless communication.</p> Methods <p>We exploit the distinct operational frequency bands of the induction coil and the spiral antenna. By implementing separate, optimized feeding mechanisms—specifically, inductive feeding for the low-frequency magnetic sensing function and capacitive feeding for the high-frequency antenna function—we achieve functional decoupling on a shared conformal coil structure. This approach allows both subsystems to operate independently without significant mutual interference.</p> Results <p>Experimental characterization of the fabricated device validates the proposed design. The results demonstrate that the single, shared coil successfully performs dual functions: it exhibits the required sensitivity and response as a magnetic induction coil while simultaneously meeting the radiation and impedance matching criteria of a spiral antenna for wireless data transmission.</p> Conclusions <p>We have successfully developed a magnetic field sensing device with a fully conformal integrated antenna. The presented design, based on differentiated feeding strategies, effectively solves the co-design problem, enabling significant miniaturization and integration for next-generation wireless magnetic sensor nodes. This work provides a practical and efficient pathway for implementing compact, multifunctional sensors in advanced IoT and monitoring systems.</p>