# Telemetry and Sensing Using a Dual-Element Implantable MIMO Antenna System

## TL;DR

This paper introduces a compact MIMO antenna system for high-speed communication and real-time sensing in biomedical implants, particularly for monitoring gastrointestinal diseases.

## Contribution

A novel dual-element MIMO antenna system with sensing capabilities for biomedical implants is proposed, achieving miniaturization and high performance.

## Key findings

- The MIMO system achieves a peak gain of −25.1 dBi and isolation levels above 27.9 dB despite its small size.
- The system outperforms single-element antennas at an SNR of 20 dB.
- The antenna can sense changes in tissue permittivity, enabling real-time physiological monitoring.

## Abstract

Diseases of the gastrointestinal tract (GI) represent a major global health burden, leading to more than eight million deaths each year, largely driven by malignant conditions such as cancers and tumors. Early detection of such conditions can significantly improve survival rates. In this work, we present a compact two-port MIMO topology for high-speed telemetry and sensing. This system integrates two identical antennas, each operating at 915 MHz, positioned only 0.55 mm apart. It has just 11.9 mm3 (6.9 mm × 6.9 mm × 0.25 mm) volume, achieved through the use of meandered resonator and a high-dielectric laminate for miniaturization. Despite its small size, the design delivers a measured peak gain of −25.1 dBi at resonance. Low mutual coupling in the antenna-system is made possible by maintaining an optimized spacing and introducing a slot in the ground plane, resulting in isolation levels above 27.9 dB. The MIMO configuration was evaluated using standard performance metrics, and at an SNR of 20 dB, the system reached a better performance than single-element antenna. Beyond communication, this design also functions as a sensor, with its resonant frequency shifting in response to changes in the surrounding tissue’s permittivity: enabling real-time monitoring of internal physiological changes. Throughout the sensing process, the design maintains good gain and impedance matching, making it a strong candidate for biomedical implants.