Informatics Publishing Limited

T. Narasimha Reddy ¹, P. Prakasam ¹, G. V. Subrahmanyam ¹, T. Nageswara Rao ¹, P. V. Prakash Goud ¹, K. Harish ¹, V. V. S. Gurunadha Rao ², C. P. Gupta ¹

Affiliations
1 Groundwater Department, Andhra Pradesh, BRKR Govt. Offices Complex, Hyderabad-500 029, IN
2 National Geophysical Research Institute, Hyderabad-500 007, IN

Abstract

Dulapally watershed in granitic terrain covers about 34 sq. km lying north of Hyderabad City in semi-arid tropics. Groundwater recharge has been estimated considering the soil-plant and agroclimatological conditions from daily rainfall and pan evoporation data during 1974 to 1990. The average annual recharge over 16 years worked out to be 124 mm. The temporal variation of the recharge estimates have been validated through simulation of well hydrographs in a nested squares finite difference aquifer model by feeding them as temporal input during transient condition.

Keywords

Hydrogeology, Groundwater, Aquifer, Granitic Terrain, Andhra Pradesh.

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B. Rajini ¹, G. V. Subrahmanyam ²

Affiliations
1 VR Siddhartha Engineering College, Vijayawada, IN
2 ANU, Guntur, IN

Abstract

In recent years, the application of radio frequency identification (RFID) operating in the ultra-high frequency (UHF) band (860-960MHz) are expanding exponentially, due to the advantages such as long reading distance, high data transfer rate, and small tag size. So the design of a CP tag antenna with broadband characteristic is presently one of the most challenging topics. This project presents a square patch passive RFID tag antenna designed for UHF band. To achieve compact size broadband and circular polarization (CP) radiation, the square patch is embedded with a cross slot, while an L-shaped open-end microstrip line coupled to the patch. By selecting an appropriate length for the microstrip line and its coupling distance with the radiating element, easy control on the input impedance of the designed tag antenna which leads to excellent impedance matching is achieved. The measured 10-dB return-loss bandwidth of the tag antenna is 27MHz (from 901-928 MHz).

Keywords

Circularly Polarization, Microstrip Antenna, Radio Frequency Identification (RFID), Tag Antenna.

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