Low Insertion-Loss Single-Pole–Double-Throw Reduced-Size Quarter-Wavelength HEMT Bandpass Filter Integrated Switches

Abstract

This paper proposes a circuit topology which reduces the chip size of single-pole-double-throw (SPDT) quarter-wavelength bandpass filter-integrated switches (FIS). A 40-GHz mHEMT MMIC SPDT switch has been implemented and demonstrates a measured insertion loss lower than 1 dB and an isolation better than 30 dB. Another 50-GHz pHEMT MMIC SPDT achieves 1.5 dB insertion loss and 22 dB isolation. The low insertion loss and high isolation shows that the circuit performance is improved along with the reduction of the size. The systematic design approach of the reduced-size FIS is described, together with the analysis of the insertion loss and isolation.

28 GHz GaAs pHEMT MMICs and RF front‐end module for 5G communication systems

“…Although the conventional series‐shunt switch topology has good isolation and low insertion loss, it suffers from the high insertion loss and poor isolation at the very high frequency more than 20 GHz because of the parasitic capacitances and inductances of small series lines . To overcome these problems, several low loss and high isolation topologies combined with shunt FET and quarter‐wave lines have been reported . In this article, the λ /4 double shunt‐FET structure is employed.…”

“…6 To overcome these problems, several low loss and high isolation topologies combined with shunt FET and quarter-wave lines have been reported. 7,8 In this article, the λ/4 double shunt-FET structure is employed. Since it has no series FET, low insertion loss is possible and high isolation is also achievable by optimizing the shunt branch design parameters of FET and parallel resonant lines.…”

Absorptive Filter Integrated Single Pole Double Throw Switch Using Switchable T-Shape Resonator for Iot Applications

“…Filter-integrated switch (FIS) as depicted in Figure 1 is another integrated/multifunction device. From the year 2006 onwards, numerous studies have reported filter-integrated double pole double throw (DPDT) switch [5], single pole single throw (SPST) switch [6][7][8], and SPDT switch [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24]. In order to produce FISs and integrate BPF with SPDT switch in one device, several techniques have been used, such as dielectric resonators (DRs) [15], LC resonators [11], substrate integrated suspended line (SISL) [30], and common shorted stepped-impedance resonator (CSSIR) [25].…”

Compact Single-Pole-Double-Throw Switchable Bandpass Filter Based on Multicoupled Line

“…Due to the employment of impedance transformer, the circuit size is large for low frequency applications. To reduce the circuit size, capacitively loaded transmission line resonator can be adopted as in [3]. A bandpass switchplexer based on the direct connection of two switchable parallel-coupled BPF is proposed in [4], but the circuit size is still large.…”