A true-time-delay networks design technique. Issue 2 (6th November 2014)

• Record Type: Journal Article
• Authors: Leggieri, Alberto; Passi, Davide; Di Paolo, Franco
• Is Part Of: International journal of microwave and wireless technologies. Volume 8:Issue 2(2016)
• Page Start: 155
• Page End: 164
• Publication Date: 2014-11-06
• Subjects: Active array antennas and components, -- Circuit design and applications, -- True time delay; Wireless communication systems -- Periodicals; Microwave circuits -- Periodicals; Radio frequency -- Periodicals; 621.381305
• DOI: 10.1017/S1759078714001408
• Languages: English
• ISSNs: 1759-0787

Abstract

Abstract : This paper proposes a technique to design wide band switched-line (SL) true-time-delay (TTD) networks, commonly used for phased array antenna (PAA) applications. This study investigates the constant-delay behavior of switched-line phase shifters based on single-pole double-throw (SPDT) switches. Circuit sizing starts by considering the effective S-parameters of the switches, to use their non-idealities as an integral part of the phase shift linearly dependent to the frequency and by considering, from the beginning, the possible spatial positioning of elements that allows the circuit feasibility as a design target. The aim of this study is to provide a technique suitable for the design of well-matched TTD networks with a flat delay in wide bandwidth. In this paper, we propose new design formulas for which we show a single-frequency implementation. A computational strategy is used to obtain numerical solutions of the derived equations with this study. Finally, a monolithic X-band TTD circuit example is shown.