Diversity Monopulse Antenna Based on a Dual-Frequency and Dual Mode CRLH Rat-Race Coupler

Abstract

Abstract-A diversity monopulse antenna is presented in this paper. This monopulse antenna is based on a dual frequency dual mode ratrace coupler that has been designed by using Composite Right/Left Handed (CRLH) Transmission Lines (TL). The device has two input ports while the (Σ) and (Δ) outputs are interchangable at either of the two operating frequencies. In this way the monopulse antenna can work at two different frequencies with two sets of radiation patterns, Σ and Δ. In addition, there is no need of diplexing to separate the (Σ) and (Δ) radiation patterns since these patterns at either frequency are directly obtained at different ports. The dual frequency dual mode rat-race requires that the phase delay of the CRLH lines must be different at either working frequency. As an example of an application, a 950 MHz/1.8 GHz dual-band dual-mode rat-race coupler is shown.

Dual-composite right–left-handed transmission lines for the design of compact diplexers

“…This means that &>C2R > ^taL-If this is introduced in (11) it leads to the following transcendent equation (see (12))…”

“…Other original planar (but rather complex and non-compact) topology for diplexer designs has been proposed in [10]. Recently, in [11] a diplexer based on non-conventional dual-mode rat race coupler has been proposed. Its main drawback is its non-compactness, especially when frequencies are low.…”

Design of Cmos Quadrature Vco Using on-Chip Trans-Directional Couplers

“…Thus, it has the benefit of DC isolation between input and output ports. And it does not use the composite right/left handed structure [17][18][19][20]. When connected to active circuits, it is possible to utilize this feature to save DC blocking circuits.…”

Directional Sensitive Modulation Signal Transmitted by Monopulse Cassegrain Antenna for Physical Layer Secure Communication

“…The Monopulse Cassegrain antenna is widely used for search-andtrack purpose in modern radar system [1][2][3][4]. The sum beam and two spatially orthogonal difference beams receive the reflected signal, simultaneously, to determine the directional information of the target based on the principle of Monopulse direction-finding.…”