Ph.D, M.Tech

Dr. Natarajamani S. currently serves as Assistant Professor at the Department of Electronics and Communication Engineering, Amrita School of Engineering, Coimbatore Campus. He joined Amrita Vishwa Vidyapeetham in July 2015.

Research Expertise

Current research project

  • Antennas for emerging wireless communications

Ongoing PG ad UG projects

  • Reconfigurable planar antennas
  • Rectenna for  wireless power transmission

Proposed research opportunities for prospective researchers

  •  Design of miniature optimal antennas for IoT applications


  • Microwave engineering
  • Antenna theory analysis and design
  • Transmission lines and radiating systems
  • Radio frequency circuit design
  • Microwave device and circuits


Publication Type: Journal Article

Year of Publication Title


Dr. Natarajamani S., “Some Studies on Designs of Planar Antennas for UWB Applications”, 2014.[Abstract]

In Ultra-Wideband (UWB) wireless system, considerable research efforts have been put into the design of UWB antennas and communication systems. These UWB antennas are essential for providing wireless wideband communications based on the use of very narrow pulses on the order of nanoseconds, covering a very wide bandwidth in the frequency domain and over very short distance at very low power densities. Also it is well known that, in traditional narrow-band communications, multiple antenna systems offer attractive aspects in wireless communication by means of Multiple-Input Multiple-Output (MIMO) techniques. These techniques either give out high channel capacities through spatial multiplexing, or offer an increase of link robustness. The present work deals with four new compact broadband antennas, suitable for portable applications are designed and characterized, namely- octagon shaped monopole, semicircular disk monopole, semi-octagon shaped diversity, semi-circular diversity. The performances of these designs have been studied using standard simulation tools used in industry or academy and experimentally verified. One of the major contributions of the thesis lies in the analysis of the frequency and time-domain response of the designed UWB antennas to confirm their suitability for portable pulsed-UWB system. A technique to avoid narrow band interference by etching narrow slot resonators on the antenna is also proposed and their effects on a nano-second pulse have been investigated. More »»


Dr. Natarajamani S., Behera, S. K., and Patra, S. K., “Planar ultra-wideband fractal antenna with 3.4 and 5.5 GHz dual band-notched characteristics”, International Journal of Signal and Imaging Systems Engineering, vol. 6, no. 1, pp. 46-51, 2013.[Abstract]

A simple and compact coplanar waveguide (CPW)-fed ultra wideband (UWB) antenna is presented. The proposed antenna consists of a circular patch with triangular slot, which is etched onto FR4 Printed Circuit Board (PCB) with overall size of 39.2 × 43.5 × 1.6 mm³. The simulated and measurement results shown that the antenna achieves good impedance matching, consistent gain and stable radiation patterns. Extended UWB antenna with notch band (3.3-3.6 GHz & 5-6 GHz) design are also presented as a desirable feature for UWB application. More »»


Dr. Natarajamani S., Behera, S. K., and Patra, S. K., “A Compact planar diversity antennas for ultra wideband application with band notched function”, Microwave and optical technology letters ( Willey Publication), vol. 55, 2013.[Abstract]

A compact two-element diversity planar antenna for ultra-wideband (UWB) application with band-notch function is proposed. By adapting two symmetrical rectangular patches with three bevels cutting in the edge of the radiators, the antenna provides wideband impedance matching characteristics over the desired frequency range. The wideband isolation can be achieved through uniform branch length ratio used in the ground plane. Measured S-parameters show that the antenna is able to cover the entire UWB band from 3.1–10.6 GHz and good isolation of less than -25 dB. Also it has a band-notch function to avoid overlap with the 3.5 GHz WiMAX band. The radiation pattern, realized gain, envelope correlation, and pulse handling capacity are measured. From the results, it is observed that the proposed diversity antenna can be suitable for UWB application. More »»


Dr. Natarajamani S., Behera, S. Kumar, and Patra, S. Kumar, “A triple band-notched planar antenna for UWB applications”, Journal of Electromagnetic Waves and Applications, vol. 27, pp. 1178-1186, 2013.[Abstract]

A compact planar microstrip-fed ultra wideband antenna for triple bands is presented and analyzed. The proposed antenna consists of semi-circular shaped radiating patch with two I-shaped stubs. It provides a wide bandwidth of 3.05–11.7 GHz. A pair of spiral loop resonators merges with radiating patch to create the first notched band in 3.3–3.7 GHz for the WiMAX system. In addition, integrated microstrip resonators are coupled with ground to generate the second- and third-notched bands in 5.2–5.4 GHz for lower WLAN and 5.7–6 GHz for upper WLAN, respectively. Experimental results of the proposed antenna exhibit good radiation pattern, stable gain, and consistent group delay performances. The time domain behavior of the antenna with and without resonator is analyzed. More »»


P. Mahender, Dr. Natarajamani S., and .K.Behera., S., “H-Shaped Dielectric Resonator Antennafor UWB application”, 2011.[Abstract]

The design of Ultra wideband dielectric resonator antenna with low dielectric constant is presented in this article. The antenna consists of H-Shape dielectric resonator (DR) fed by Microstrip line and a slotted ground. Parametric studies, time domain analysis of the antenna are presented. The parameters are designed and simulated using CST Microwave studio. The constant group delay, path loss and the calculated correlation factor shows that the antenna is well suited for UWB applications. More »»


Dr. Natarajamani S., Behera, S. K., and Patra, S. K., “A triple band-notched planar monopole antenna for ultra-wide band applications”, Microwave and optical technology letters (Willey Publication), vol. 54, no. 2, pp. 539–543, 2011.[Abstract]

This article presents the compact planar antenna with 3.5/5.5/8.2 GHz triple band-notched characteristics. The antenna consists of an octagon shape patch with 50 Ω transmission line. By etching two C-shaped slots in the patch and adding pair of L-shaped resonator coupled to the radiating patch, band-rejected filtering properties in the WiMAX/WLAN/ITU bands are achieved. The proposed ultrawide band (UWB) antenna is optimized to operate in the frequency band from 3 to 11 GHz for VSWR < 2. Measured results confirm that the antenna is suitable for UWB applications because of its compact size and high performance. More »»

Publication Type: Conference Paper

Year of Publication Title


A. K Reddy, Dr. Natarajamani S., and Behera, S. K., “Antipodal vivaldi antenna UWB antenna with 5.5 GHz band-notch characteristics”, in International Conference on Computing, Electronics and Electrical Technologies [ICCEET] , 2012.[Abstract]

This paper presents a compact antipodal Vivaldi antenna for UWB allocation with band dispersion characteristics. The main purpose of this design is the reduction of three parameter such as transient distortion, reflection co-efficient & surface wave loss. The proposed antenna has the capability to operate over the bandwidth 3-11GHz at return loss More »»


Dr. Natarajamani S., .K.Behera, S., and .K.Patra, S., “Planar UWB Fractal Antenna with Band-Notched Characteristics”, in International Conference on Electronic Systems (ICES-2011), 2011.


Dr. Natarajamani S., .S.K, B., and .S.K, P., “A Planar UWB antenna with Band notch characteristics”, in International Conference on Electronic Systems, 2011.


Dr. Natarajamani S., Behera, S. K., and Patra, S. K., “Planar ultrawideband antenna with 5.5GHz band dispensation characteristics”, in 2010 Annual IEEE India Conference (INDICON), 2010.[Abstract]

A compact and simple design of a CPW-fed planar antenna for ultra-wideband application with a band-notch characteristic is presented. The proposed antenna consists of a rectangular metal patch on a printed circuit board fed by a 50Ω coplanar waveguide (CPW) with an overall size of 32×30×1.6mm3. By cutting a C-shaped slot in the rectangular radiating patch, a frequency band notch will be created. The proposed antenna yields an impedance bandwidth of 3.1-10.6GHz with VSWR≤2, except the bandwidth of 5-6GHz for WLAN. The bandwidth and central frequency of the notched band can be adjusted with ease by proper selection of C-shaped slot. The parameters simulated by CST Microwave Studio. The antenna is successfully designed and simulated. Showing broadband matched impedance, stable gain and radiation patterns over an operating bandwidth. More »»


Dr. Natarajamani S., .S.K, B., and .S.K, P., “Compact Slot Antenna for UWB Application and Band-Notch Design”, in IEEE 5th International Conference on Computational Intelligence and computer networks, 2010.


M. .P, Dr. Natarajamani S., and .S.K, B., “Inverted U-Shaped Dielectric Resonator Antenna for WLAN”, in IEEE International Conference on Communication Control and Computing Technology, india, 2010.


Dr. Natarajamani S., .S.K, B., and .S.K, P., “Compact CPW-fed Dual-Band Antenna for WLAN/UWB Application”, in IEEE International Conference on Communication Control and Computing Technology, 2010.


Dr. Natarajamani S., .S.K, B., and .S.K, P., “A Compact Wide band Patch Antenna for WLAN Application”, in IEEE second International Conference on Computing, Communication and Networking Technologies, 2010.


Dr. Natarajamani S., .S.K, B., .S.K, P., and .R.K, M., “CPW-FED Octagon shape slot Antenna for UWB Application”, in IEEE 5th International conference on Microwaves, Antenna Propagation and Remote Sensing, India., 2009.


Dr. Natarajamani S., .S.K, B., and .R.K, M., “Design of Multi slotted and Multi frequency patch Antenna”, in IEEE Applied Electromagnetic Conference, India, 2009.

Faculty Research Interest: