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A compact, dual wide-band circularly polarized, modified square ring slot antenna for C and Ku band applications
This paper presents a compact microstrip antenna using FR-4 substrate for dual band circularly polarized operation using a modified square ring slot in the ground plane with microstrip line feed. Simulation of the impedance characteristic and radiation characteristic for the proposed antenna is carried out using commercially available HFSS software. The simulated data validate measured results and
MRF volume 11 issue 1 Cover and Back matter
MRF volume 11 issue 1 Cover and Front matter
Addendum ? Miniaturized branch-line coupler based on slow-wave microstrip lines
Wideband filtering power dividers with wide stopband rejection
A series of novel wideband filtering power dividers (WFPDs) with wide stopband rejection performances is proposed in this paper. The proposed WFPD structure consists of a parallel-coupled line, two transmission line (TL) sections, four loading terminations, and an isolation resistor. The coupled line is applied at the input port to provide wideband impedance transformation, while different types o
Prediction on operating range of passive troposcatter detection system
Electromagnetic wave of enemy radar propagated by troposcatter is a valuable candidate for beyond line-of-sight detection. There is no analytical study considering the operating range of passive troposcatter detection system. In this paper, we study the way to predict the operating range, which is dominated by propagation loss. The key propagation loss models including statistic model and real-tim
Time-domain analysis of a CRLH coupled-line coupler using the CN-FDTD method
In this study, the implicit Crank?Nicolson finite-difference time-domain (CN-FDTD) method is applied to discretize the governing telegrapher's equations of a composite right-/left-handed (CRLH) coupled-line coupler. The unconditionally stable CN-FDTD is compared with the conventional leap-frog (LF) FDTD method. The results obtained from the CN-FDTD scheme show up to 10 times increase in the tempor
Design and development of 2 kW, 3 dB hybrid coupler for the prototype Ion Cyclotron Resonance Frequency (ICRF) system
Design and development of 2 kW, 3 dB tandem hybrid coupler for the frequency range of 155?225 MHz has been presented in this paper. The developed 3 dB coupler is to be used in a prototype of Ion Cyclotron Resonance Frequency (ICRF) system of Tokamak, which has been developed to test the resilience of ICRF network during continuously variable RF load excursions. The 3 dB coupler divides the RF powe
An autofocusing method for imaging the targets for TWI radar systems with correction of thickness and dielectric constant of wall
In through the wall imaging systems, wall parameters like its thickness and dielectric constant play an important role in the true and correct image formation of an object behind the wall made of various materials like brick cement, wood, plastic, etc. Incorrect estimation of these parameters leads to dislocation of the object and smearing or blurriness of the image too. A new autofocusing techniq
Dual band- dual polarized planar inverted F-antenna for MBAN applications
A planar inverted F-Antenna with the dual band-dual polarization property is presented for medical body area networks applications. The designed antenna covers the 2.45 GHz industrial, scientific and medical, 4 G long term evolution (2.5?2.69 GHz) bands for ON body communication and Wi-Fi and WLAN (3.5?3.6 GHz) bands for OFF body communication. At the lower band, an equivalent offset fed magnetic