1. Introduction Monolithic-type microwave integrated circuits used in various communication devices have many microstrip discontinuities such as ends, bends, gaps, and width changes. Such circuits are usually designed assuming no radiation from these discontinuities. However, radiation always occurs more or less because the structure is theoretically of open type. Recent trend of use of higher ...

Over the past years microstrip resonators have been widely used in the range of microwave frequencies. In general these structures are poor radiators, but by proper design the radiation performance can be improved and these structures can be used as antenna elements (Damiano & Papiernik, 1994). In recent years microstrip patch antennas became one of the most popular antenna types for use in aer...

Abstract : Microstrip antennas or patch antennas are popular for their attractive features such as low profile, low weight, low cost, ease of fabrication and integration with RF devices. Micro strip antennas have been found favorable because they are inexpensive to manufacture and compatible with monolithic microwave integrated circuit designs (MMIC). They are usually employed at UHF and higher...

A retrodirective transponder based on a novel compact phaseconjugating mixer with conversion gain has been developed. The active circuit uses one port for both incoming and outgoing signals, enabling a reduction of circuit size, and the balanced structure provides suppression of undesired signals. By using a modulated local oscillator, the circuit can modulate the received signal in order to re...

Abstract—In this paper, the design and development of a novel active antenna including circuits for Ultra-wide band (UWB) pulse generation and transmission have been described. In this design a pulse with pulse-width approximately 150 ps and amplitude 500 mV (peak-topeak) was generated using a single high electron mobility transistor (HEMT) as the active device (and an optional Schottky diode f...