Integrated radio‐frequency/wireless coil design for simultaneous MR image acquisition and wireless communication

Abstract

Purpose An innovative radio‐frequency (RF) coil design that allows RF currents both at the Larmor frequency and in a wireless communication band to flow on the same coil is proposed to enable simultaneous MRI signal reception and wireless data transfer, thereby minimizing the number of wired connections in the scanner without requiring any modifications or additional hardware within the scanner bore. Methods As a first application, the proposed integrated RF/wireless coil design was further combined with an integrated RF/shim coil design to perform not only MR image acquisition and wireless data transfer, but also localized B0 shimming with a single coil. Proof‐of‐concept phantom experiments were conducted with such a coil to demonstrate its ability to simultaneously perform these three functions, while maintaining the RF performance, wireless data integrity, and B0 shimming performance. Results Performing wirelessly controlled shimming of localized B0 inhomogeneities with the coil substantially reduced the B0 root‐mean‐square error (>70%) and geometric distortions in echo‐planar images without degrading the image quality, signal‐to‐noise ratio (<1.7%), or wireless data throughput (maximum variance = 0.04 Mbps) of the coil. Conclusions The RF/wireless coil design can provide a solution for wireless data transfer that can be easily integrated into existing MRI scanners for a variety of applications.

Wireless Reconfigurable RF Detector Array for Focal and Multiregional Signal Enhancement

“…Unlike passive inductive arrays [28,29] whose individual detector elements cannot be wirelessly controlled, our reconfigurable array can conveniently switch between selective and simultaneous activation to highlight multiple detection regions in real time, enabling convenient multiplexing [30][31][32] of a single-channel MRI scanner without the need for expensive console upgrade. Unlike several other active arrays [33][34][35][36][37] that require at least 100 mW of DC power to operate complicated on-board microcontrollers, our reconfigurable array relies on simple nonlinear circuits that can operate by less than 10 mW of wireless power, thus creating a wireless signal link between internal detectors (that are optimized for focal tissues) and the generic detector (that is commonly available on standard MRI scanners). Besides sensitivity enhancement for multimodal imaging of rodent brains, this wireless reconfigurable detector array will also be useful to improve the operation flexibility of clinical MRI, e.g.…”

Recent Advances in Radio‐Frequency Coil Technologies: Flexible, Wireless, and Integrated Coil Arrays

“…5) antennas and low-power electronics 38,39,47 to wirelessly transfer data in the scanner bore, which can reliably provide data rates between 11 Mbps (802.11b) and 500 Mbps (802.11 ad) with low bit-error. 38 Excitingly, proof-of-concept MRI experiments have first been conducted to wirelessly transfer data at low data rates (eg, <100 Mbps) 48,49 and more recently with WiGig at high data rates (eg, >100 Mbps) suitable for RF coil array applications 47 (Fig. 5b), which demonstrated the ability of these methods to wirelessly transmit data in the bore without decreasing the image SNR.…”

“…Most peripheral devices, as adopted by industries thus far, are made wireless by using additional antenna systems and electronics in the scanner bore to transmit sensor data outside of the scanner room, which has the same aforementioned disadvantages as for RF coil arrays. Alternatively, a new integrated RF/wireless (iRFW) coil design 48 can be used to simultaneously acquire MR images and wirelessly transmit sensor data outside of the scanner bore by allowing RF currents both at the Larmor frequency (eg, 127.7 MHz for a 3T scanner) and within a wireless communication band (eg, 2.4 GHz for WiFi) to flow on the conductors of the same coil element (Fig. 6b), which eliminates the need for additional antenna systems in the scanner bore.…”

“…7g), thereby enabling MR imaging, wireless communication, and localized B 0 shimming, respectively, with a single coil element. 48 This wireless iPRES (iPRES-W) coil design thus enables wireless localized B 0 shimming using DC currents that are supplied by an MR-compatible battery pack within the scanner bore and wirelessly controlled by a computer located outside the scanner room. 84 In the dual-stream iPRES-W coil design, two iPRES-W coil elements (along with additional iPRES coil elements) are used to enable two concurrent wireless applications, such as wireless localized B 0 shimming and wireless respiratory monitoring with a respiratory belt.…”

Perspectives in Wireless Radio Frequency Coil Development for Magnetic Resonance Imaging

“…Several MRI applications benefit from localized on-coil B 0 shimming with DC currents on the RF coil elements compensating for B 0 inhomogeneities [66]. High shim currents themselves cannot be wirelessly transmitted but can be wirelessly controlled, which has been successfully demonstrated by 2.4 GHz Wi-Fi communication [67], using the RF coil itself as a wireless transponder.…”