Capacitive Parameter Estimation of Passive Telemetry RF Sensor System Using RLS Algorithm

RLS 알고리즘을 이용한 원격 RF 센서 시스템의 정전용량 파라메타 추정

  • 김경엽 (동아대 공대 전기공학과) ;
  • 이준탁 (동아대 공대 전기공학과)
  • Published : 2008.05.01

Abstract

In this paper, Capacitive Telemetry RF Sensor System using Recursive Least Square (RLS) algorithm was proposed. General Telemetry RF Sensor System means that it should be "wireless", "implantable" and "batterless". Conventional Telemetry RF Sensor System adopts Integrated Circuit type, but there are many defects like complexity of structure and the limitation of large power consumption in some cases. In order to overcome these disadvantages, Telemetry RF Sensor System based on inductive coupling principle was proposed in this paper. Proposed Telemetry RF Sensor System is very simple because it consists of R, L and C and measures the changes of environment like pressure and humidity in the type of capacitive value. This system adopted RLS algorithm for estimation of this capacitive parameter. For the purpose of applying RLS algorithm, proposed system was mathematically modelled with phasor method and was quasi-linearized. As two parameters such as phase and amplitude of output voltage for estimation were needed, Phase Difference Detector and Amplitude Detector were proposed respectively which were implemented using TMS320C2812 made by Texas Instrument. Finally, It is verified that the capacitance of proposed telemetry RF Sensor System using RLS algorithm can be estimated efficiently under noisy environment.

Keywords

Recursive Least Square Algorithm;Telemetry RF Sensor;Inductive Coupling;TMS320C2812;Phasor Method

References

  1. O.Akar, T.Akin, K.Najafi, "A Wireless batch sealed absolute Capacitive Pressure Sensor",Sensor and Actuators, A 95 pp29-38, 2001 https://doi.org/10.1016/S0924-4247(01)00753-1
  2. http://www.microstrain.com/applications.aspx
  3. T.Varpula, and O.Jaakkola, "Low Cost Wireless RF Sensors", Automation Technology Review, pp.12-17, 2001
  4. American National Standards Institute, Safety Levelof Electromagnetic Radiation with respect to Personnel, ANSI C95.1-1974, IEEE, 1974
  5. 조재신, "RFID 지식재산권 동향과 대응방안", 특허청, 2005
  6. 천재영, 조평동, "실리콘기반 압력센서기술동향", ITFIND 주간기술동향, 1225권호, 2005
  7. J.R.Jang, C.Sun, E.Mizuani, Neuro-Fuzzy and Soft Computing, Prentice-Hall International, Inc. pp.95-117, 1997
  8. T.Suzuki, "Performance of Polyimide-Based Humidity Sensor", Microelectronic Engineering Research Conference, 2001
  9. HUMIREL, HS1100/HS1101 Technical Data, HPC001 Rev.7 June 2002
  10. T.J.Hapster, B.Stark, K.Najafi, "A Passive Wireless Integrated Humidity Sensor", The 14th IEEE International Conference on MEMS, pp.553-557,2001