Quad-Band 1 × 4 Linear MIMO Antenna for Millimeter-Wave, Wearable and Biomedical Telemetry Applications

Area of Science:

• Electrical Engineering
• Antenna Theory
• Biomedical Engineering

Background:

• Millimeter-wave (mm-wave) frequencies are crucial for high-bandwidth communication, including wearable biomedical telemetry.
• Flexible antennas are essential for comfortable and reliable integration into wearable devices.
• Existing mm-wave antennas may lack the multi-band capabilities and flexibility required for advanced biomedical applications.

Purpose of the Study:

• To design and evaluate a flexible 1x4 linear MIMO array antenna operating in multiple mm-wave bands.
• To assess the antenna's performance for wearable biomedical telemetry applications, considering gain, efficiency, and diversity.
• To validate the antenna's robustness under bending conditions and analyze its safety (SAR) and communication range.

Main Methods:

• A modified slot-loaded triangular patch antenna with cross-shaped slots in the ground plane was designed on a flexible substrate.
• The antenna was configured as a 1x4 linear MIMO array for enhanced performance.
• Simulations and analyses were performed for S-parameters, gain, radiation efficiency, diversity metrics (ECC, DG, CCL), bending effects, Specific Absorption Rate (SAR), and link budget.

Main Results:

• The antenna achieved multi-band operation across 26.28-27.36 GHz, 27.94-28.62 GHz, 32.33-33.08 GHz, and 37.59-39.47 GHz.
• Peak gains ranged from 5.58 to 8.58 dBi, with radiation efficiency exceeding 75%.
• Excellent diversity metrics (ECC < 0.02, DG > 9.97 dB) and stable performance under bending were observed. SAR values were within acceptable limits, and a link budget analysis showed a 70m range.

Conclusions:

• The proposed flexible mm-wave MIMO antenna is well-suited for wearable biomedical telemetry due to its multi-band operation, high performance, and flexibility.
• The antenna's design effectively addresses impedance matching and diversity requirements for mm-wave 5G applications.
• The validated performance, including bending stability and safety, confirms its potential for practical implementation in biomedical devices.