Glass-Integrated Single- and Dual-Band Bandpass Filters

Combined signal‐interference/split‐type microwave multi‐band bandpass filters

“…White-space communications can also take benefit of this scenario by enabling the transmission of higher date rates by using non-adjacent frequency regions at the same time [6,7]. As of today, the interest of multi-band BPFs is fairly evidenced by the rich variety of solutions available in the technical literature for different RF technologies, such as planar [8][9][10], 3-D/waveguide [11][12][13][14], substrateintegrated waveguide [15][16][17], superconductor [18,19], and active/passive-integrated-circuit technologies [20][21][22].…”

Multi‐band glass‐integrated bandpass filters for new radio (NR) communications

“…Although acoustic-wave filters such as the ones based on surface acoustic wave (SAW) resonators and bulk acoustic (BAW) resonators have been the major RF filtering technology for cellular communications, they are limited to narrow-band single-band transfer functions and frequencies <2 GHz. Integrated passive devices (IPDs) based filters using silicon [1][2][3], microwave monolithic integrated circuits (MMIC) [4], or low-temperature co-fired ceramic (LTCC) [5,6] and glass substrates [7][8][9][10][11][12] functionalize significantly wider BWs, and are suitable for higher frequencies; however, they exhibit lower quality-factor than the SAW/BAW filters and are significantly larger in size. Among the existing IPD technologies, glass-based IPDs exhibit competitive RF performance for both FR1 [7][8][9][10][11] and FR2 [12] applications.…”

“…Integrated passive devices (IPDs) based filters using silicon [1][2][3], microwave monolithic integrated circuits (MMIC) [4], or low-temperature co-fired ceramic (LTCC) [5,6] and glass substrates [7][8][9][10][11][12] functionalize significantly wider BWs, and are suitable for higher frequencies; however, they exhibit lower quality-factor than the SAW/BAW filters and are significantly larger in size. Among the existing IPD technologies, glass-based IPDs exhibit competitive RF performance for both FR1 [7][8][9][10][11] and FR2 [12] applications. Notable demonstrations of these trends include single-band quasi-elliptic bandpass filters (BPFs) for n77 and n79 bands [7,8] and inverter-less single and dual-band BPFs configurations in [10].…”

“…Among the existing IPD technologies, glass-based IPDs exhibit competitive RF performance for both FR1 [7][8][9][10][11] and FR2 [12] applications. Notable demonstrations of these trends include single-band quasi-elliptic bandpass filters (BPFs) for n77 and n79 bands [7,8] and inverter-less single and dual-band BPFs configurations in [10]. In yet another configuration, thin-film glass-based IPDs on both sides of glass substrates [9] have been demonstrated for the realization of small single BPFs, however with very limited selectivity.…”

“…In yet another configuration, thin-film glass-based IPDs on both sides of glass substrates [9] have been demonstrated for the realization of small single BPFs, however with very limited selectivity. Overall, with the exception of the work in [10], all the existing IPD glass filtering concepts are single-band creating the need for multi-band configurations.…”