Doppler Ultrasound as the gold standard for noninvasive arterial pulsation monitoring has limitations such as dependency on the operator and absence of acoustic window in some patients. Recently, mm-wave has been propounded as an alternative modality for biomedical diagnostics. However, heartbeat monitoring using mm-wave modality has been experimentally investigated only for external carotid artery, and its usage for deeper arteries has not been proved, yet. This study investigates the feasibility of mm-waves in the monitoring of non-superficial arteries. A continuous-wave (CW) reflectometer sensor is used for sensing pulsations exploiting the Doppler effect. The artery mimicking tube passes through an artificial agar-oil skin phantom. A peristaltic pump circulates the liquid through a tube. An antenna is placed in direct contact with the phantom without any coupling liquid. First, we investigate the optimum frequency of the given antenna in its impedance bandwidth [16 GHz-20 GHz]. Using the optimum frequency, the pulsation of an ar-tery with a 1.6 mm diameter, placed in the depth of 16 mm, and has less than 0.02 mm radial oscillation amplitude was easily detectable.
2. Li, Y., P. Segers, J. Dirckx, and R. Baets, "On-chip laser Doppler vibrometer for arterial pulse wave velocity measurement," Biomed. Opt. Express, Vol. 4, No. 7, 1229-1235, 2013.
3. Sun, C.-K., "Cardio-ankle vascular index (CAVI) as an indicator of arterial stiffness," Dovepress, No. 6, 27-38, 2013.
4. Boutry, C. M., et al., "Biodegradable and flexible arterial-pulse sesnor for the wireless monitoring of blood flow," Nat. Biomed. Eng., Vol. 3, No. 1, 2019.
5. Avolio, A. P., M. Butlin, and A. Walsh, "Arterial blood pressure measurement and pulse wave analysis --- Their role in enhancing cardiovascular assessment," Physiol. Meas., Vol. 31, 1-47, 2010.
6. Jayanthy, A. K., N. Sujatha, and M. R. Reddy, "Measuring blood flow: Techniques and applications --- A review," Int. J. Res. Rev. Appl. Sci., Vol. 6, No. 2, 203-216, 2011.
7. Saugel, B., et al., "Cardiac output estimation using pulse wave analysis d physiology, algorithms, and technologies: A narrative review," Br. J. Anaesth., Vol. 126, No. 1, 67-76, 2021.
8. Saugel, B., et al., "Continuous noninvasive pulse wave analysis using finger cuff technologies for arterial blood pressure and cardiac output monitoring in perioperative and intensive care medicine: A systematic review and meta-analysis," Br. J. Anaesth., Vol. 125, No. 1, 25-37, 2020.
9. Elgendi, M., et al., "The use of photoplethysmography for assessing hypertension," NPJ Digit. Med., Vol. 60, 1-11, 2019.
10. Johansson, K., H. Ahn, J. Lindhagen, and O. Lundgren, "Tissue penetration and measuring depth of laser Doppler flowmetry in the gastrointestinal application," Scand. J. Gastrology, Vol. 22, No. 9, 1081-1088, 2009.
11. Chatterjee, S., J. P. Phillips, and P. A. Kyriacou, "Monte Carlo investigation of the effect of blood volume and oxygen saturation on optical path in reflectance pulse oximetry," Biomed. Phys. Eng. Express, Vol. 2, No. 6, 1-14, 2016.
12. Ruvio, G., A. Cuccaro, R. Solimene, A. Brancaccio, B. Basile, and M. J. Ammann, "Microwave bone imaging: A preliminary scanning system for proof-of-concept," Healthc. Technol. Lett., Vol. 3, No. 3, 218-221, 2016.
13. Quail, A. W., D. B. F. Cottee, and S. W. White, "Limitations of a pulsed Doppler velocimeter for blood flow measurement in small vessels," J. Appl. Physiol., Vol. 75, No. 6, 2745-2754, 1993.
14. Libove, J., D. Schriebman, and M. Ingle, "Picosecond pulse imaging --- Uniquely promising but challenging modality for a wearable BMI," 2017 IEEE International Conference on Systems, Man, and Cybernetics (SMC), 2448-2453, 2017.
15. Libove, J., D. Schriebman, M. Ingle, and B. Wahl, "Wearable brain imager/BMI technology for structural, vascular and functional extraction," 2016 IEEE International Conference on Systems, Man, and Cybernetics (SMC), 3806-3811, 2016.
16. Deverson, S., D. H. Evans, and D. C. Bouch, "The effects of temporal bone on transcranial Doppler ultrasound beam shape," Ultrasound Med. Biol., Vol. 26, No. 2, 239-244, 2000.
17. Zhou, T., S. Member, P. M. Meaney, M. J. Pallone, S. Geimer, and K. D. Paulsen, "Microwave tomographic imaging for osteoporosis screening: A pilot clinical study," IEEE Eng. Med. Biol. Soc. 2010, 1218-1221, 2010.
18. Michimoto, I., et al., "Simulation study on the effects of cancellous bone structure in the skull on ultrasonic wave propagation," Sci. Rep., Vol. 11, No. 1, 1-12, 2021.
19. Chandra, R., H. Zhou, I. Balasingham, S. Member, and R. M. Narayanan, "On the opportunities and challenges in microwave medical sensing and imaging," IEEE Trans. Biomed. Eng., Vol. 62, No. 7, 1667-1682, 2015.
20. Meaney, P. M., et al., "Clinical microwave tomographic imaging of the calcaneus: A first-in-human case study of two subjects," IEEE Trans. Biomed. Eng., Vol. 59, No. 12, 3304-3313, 2012.
21. Amin, B., M. A. Elahi, A. Shahzad, E. Porter, B. McDermott, and M. O'Halloran, "Dielectric properties of bones for the monitoring of osteoporosis," Med. Biol. Eng. Comput., Vol. 57, No. 1, 1-13, 2019.
22. Amin, B., A. Shahzad, M. O'halloran, and M. A. Elahi, "Microwave bone imaging: A preliminary investigation on numerical bone phantoms for bone health monitoring," Sensors (Switzerland), Vol. 20, 1-21, 2020.
23. Mase, A., et al., "Non-contact and real-time measurement of heart rate and heart rate variability using microwave reflectometry," Rev. Sci. Instrum., Vol. 91, No. 1, 2020.
24. Nagae, D. and A. Mase, "Measurement of heart rate variability and stress evaluation by using microwave reflectometric vital signal sensing," Rev. Sci. Instrum., Vol. 81, No. 9, 2010.
25. Dany Obeid, G. E. Z., G. Zaharia, and S. Sadek, "Microwave Doppler radar for heartbeat detection vs electrocardiogram," Microw. Opt. Technol. Lett., Vol. 54, No. 11, 2610-2617, 2013.
26. Xu, Y., Q. Li, and Z. Tang, "Accurate and contactless vital sign detection in short time window with 24 GHz Doppler radar," J. Sensors, Vol. 2021, 1-14, 2021.
27. Shi, K., S. Schellenberger, T. Steigleder, F. Michler, and F. Lurz, "Contactless carotid pulse measurement using continuous wave radar,", 1-3, November 2018.
28. Chamaani, S., A. Akbarpour, M. Helbig, and J. Sachs, "Matrix pencil method for vital sign detection from signals acquired by microwave sensors," Sensors, Vol. 21, No. 17, 1-24, 2021.
29. Pisa, S., S. Chicarella, E. Pittella, E. Piuzzi, O. Testa, and R. Cicchetti, "A double-sideband continuous-wave radar sensor for carotid wall movement detection," IEEE Sens. J., Vol. 19, No. 10, 8162-8171, 2018.
30. Fung, Y. C. and S. C. Cowin, Biomechanics: Motion, Flow, Stress, and Growth, 1st Ed., Springer, New York, 1990.
31. Hoeks, A. P. G., P. J. Brands, F. A. M. Smeets, and R. S. Reneman, "Assesment of the distinsibility of superficial arteries," Ultrasound Med. Biol., Vol. 16, No. 2, 121-128, 1990.
32. Mynard, J. P., A. Kondiboyina, and R. Kowalski, "Measurement, analysis and interpretation of pressure/flow waves in blood vessels," Front. Physiol., Vol. 11, 1-26, 2020.
33. A-900 Peristaltic pump, [Online], Available, https://www.hll.de/12/1/AD223/MTA2NzIwNDA-w/Landgraf HLL 106720400 Landgraf HLL.html.
34. R. Corporation RO4000r Series High Frequency Circuit Materials, 2018.
35. Nikolova, N. K., "Microwave imaging for breast cancer," IEEE Microw. Mag., Vol. 12, No. 7, 78-94, 2011.
36. Nguyen, D. H., J. Ala-laurinaho, J. Moll, V. Krozer, and S. Member, "Improved sidelobe-suppression microstrip patch antenna array by uniform feeding networks," IEEE Trans. Antennas Propag., Vol. 68, No. 11, 7339-7347, 2020.
37. Nguyen, D. H., J. Moll, V. Krozer, V. Memmolo, and G. Zimmer, "Elliptical monopole antenna design for the early breast cancer imaging at high frequencies," 2021 15th European Conference on Antennas and Propagation (EuCAP), 1-4, 2021.
38. Scalise, L., A. De Leo, V. Mariani Primiani, P. Russo, D. Shahu, and G. Cerri, "Non contact monitoring of the respiration activity by electromagnetic sensing," MeMeA 2011 --- 2011 IEEE Int. Symp. Med. Meas. Appl. Proc., 418-422, May 2011.