Compact Self-Quadruplexing Antenna Based on Siw Cavity-Backed With Enhanced Isolation

Abstract

A self-quadruplexing antenna based on substrate integrated waveguide (SIW) is presented. A slot is engraved on its top surface of the SIW cavity, which generates four different resonant frequencies (around 6.54, 7.64, 8.30, and 9.60 GHz) when it is excited by four 50 Ω microstrip feed lines. Also, each resonant frequency can be controlled independently. Due to a quarter mode (QM) cavity, the antenna size becomes compact. The measured results show that the isolation between any two ports is more than 32 dB, and the estimated gain is more than 7.8 dBi at the operating frequencies. The proposed design is simple to fabricate, compact, and easy to integrate with the planner circuits.

A Quad-Band Shared-Aperture Antenna Based on Dual-Mode Composite Quarter-Mode SIW Cavity for 5G and 6G with MIMO Capability

“…The proposed antenna is designed based on a new hybrid design technique; it is based on a dual-mode composite antenna and higher-order modes of sub-mode-SIW-cavities for the first time. This is different from current techniques of sharedaperture antennas in the open literature, which are designed based on the dual-mode composite and higher-order modes of full-mode cavity antennas [30][31][32][33][34][35], while selfmultiplexing antennas are based on sub-mode cavity antennas alone, without the dual-mode concept [20][21][22][23][24][25][26][27][28][29].…”

“…First, the conventional SIW cavity-based antenna design approach [19][20][21][22][23][24][25][26][27][28][29], which has been shown to be suitable for dual-and multi-band applications [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29]. As shown in Figure 1, this approach can be implemented as a full-mode cavity antenna (Figure 1a) or a sub-mode cavity antenna (Figure 1b-d).…”

“…However, sub-mode SIW cavity antennas only provide single to dual frequencies in Mw applications with a low frequency ratio [20,22]. Second, self-multiplexing SIW cavity-based antennas are a desirable option for multiband antenna applications [23][24][25][26][27][28][29]. Self-diplexing [25,26], self-triplexing [27,28], and quadruplexing antennas [23,24,29] have been utilized to achieve dual-band, tri-band, and quad-band capabilities, respectively.…”

“…Second, self-multiplexing SIW cavity-based antennas are a desirable option for multiband antenna applications [23][24][25][26][27][28][29]. Self-diplexing [25,26], self-triplexing [27,28], and quadruplexing antennas [23,24,29] have been utilized to achieve dual-band, tri-band, and quad-band capabilities, respectively. However, these antennas are designed mainly using the multi-cavity, multi-port concept, where each individual-band cavity is powered by its own port, making the design more complicated and taking up more space [36].…”

Self‐isolated quadruplexing SIW antenna with extremely low frequency ratio for C‐band applications

“…However, the design of self-quadplexer antennas for quad-band operation with low FR (f 4 /f 1 ) is difficult, and maintaining port isolation becomes more challenging as the number of ports increases. Several self-quadplexing antennas have been proposed based on V-shaped slots, [11][12][13] U-shaped slots, 14,15 T-shaped slot, 16 different resonating patches 17 and two half mode resonators with extended slots. 18 Even though all these quadplexing antennas exhibit significant isolation, they are constrained by either the electrical size of the antenna or high FR as listed in Table 1.…”