Journal ArticleDOI
Compact forward-coupled superconducting microstrip filters for cellular communication
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TLDR
In this paper, a forward-coupled microstrip filter structure is presented for narrow-band applications in cellular communications, which consists of a parallel array of fully aligned half-wavelength resonators.Abstract:
A compact forward-coupled microstrip filter structure is presented for narrow-band applications in cellular communications. The structure consists of a parallel array of fully aligned half-wavelength resonators. Coupling is controlled by the spacing of the adjacent resonators, and is based on the even- and odd-mode phase velocity difference of coupled lines in a microstrip configuration. Two filter designs, based on the forward-coupled structure, were fabricated using YBa/sub 2/Cu/sub 3/O/sub 7/ (YBCO) high-temperature superconducting (HTS) thin films on LaAlO/sub 3/ substrates. One filter, a 9-pole 2.8% fractional-bandwidth YBCO filter at 900 MHz, has less than 0.27 dB insertion loss and better than 16 dB return loss. The other filter, a 5-pole 1.2% fractional bandwidth YBCO filter with 10-/spl Omega/ internal impedance at 2 GHz, has less than 0.35 dB insertion loss and better than 12 dB return loss. All designs showed excellent measured frequency response. >read more
Citations
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Book
Microstrip filters for RF/microwave applications
TL;DR: In this paper, the authors present a general framework for coupling matrix for Coupled Resonator Filters with short-circuited Stubs (UWB) and Cascaded Quadruplet (CQ) filters.
Journal ArticleDOI
Superconducting microwave filter systems for cellular telephone base stations
TL;DR: The underlying technologies that support HTS wireless applications, based upon the characteristic microwave properties of HTS thin films and substrates are discussed, which enable the development of a broadly deployable technology.
Patent
High-frequency device
Yoshiaki Terashima,Fumihiko Aiga,Mutsuki Yamazaki,Hiroyuki Fuke,Hiroyuki Kayano,Riichi Katoh +5 more
TL;DR: In this paper, a high-frequency device is proposed to adjust the pass-band frequency of a filter without variations in the skirt characteristic or ripple characteristic, which enables the filter to be adjusted with high accuracy.
Journal ArticleDOI
Narrowband lumped-element microstrip filters using capacitively-loaded inductors
TL;DR: In this article, a class of lumped-element filters that uses capacitively-loaded inductors to give frequency-dependent inductance values is reported. But, it is difficult to realize narrowband filters (e.g., < 0.1% fractional bandwidth) in reasonably sized microstrip form due to the very weak coupling values required.
Journal ArticleDOI
A 19-pole cellular bandpass filter using 75-mm-diameter high-temperature superconducting thin films
TL;DR: In this article, a 19-pole bandpass filter designed for the 900-MHz cellular communication band with 25-MHz bandwidth is reported using a compact forward-coupled approach in microstrip configuration.
References
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Book
Handbook of microwave integrated circuits
TL;DR: Hoffmann et al. as mentioned in this paper presented the Handbook of microwave integrated circuits (HOLA) for the purpose of measuring the pressure fields using covariance and spectral proper transformations.
Journal ArticleDOI
Low- and high-temperature superconducting microwave filters
S.H. Talisa,M.A. Janocko,C. Moskowitz,J. Talvacchio,J.F. Billing,R. Brown,D.C. Buck,C.K. Jones,Bruce R. McAvoy,G.R. Wagner,D.H. Watt +10 more
TL;DR: In this paper, low-temperature superconducting niobium thin films, deposited on single-crystal sapphire, were used to build to six-pole stripline filters with adjacent passbands and approximately 3 dB crossovers and 1.2% bandwidth.
Journal ArticleDOI
Measured performance at 77 K of superconducting microstrip resonators and filters
TL;DR: In this paper, a superconducting 4.6 GHz band-reject filter with unloaded Q greater than 15000 when operated at 77 K and 33 GHz, respectively, is presented.
Proceedings ArticleDOI
High-temperature superconductive passive microwave devices
W.G. Lyons,R.S. Withers,J.M. Hamm,Alfredo C. Anderson,P.M. Mankiewich,M.L. O'Malley,R.E. Howard,R. R. Bonetti,A. E. Williams,N. Newman +9 more
TL;DR: In this article, two important classes of passive superconductive microwave devices are described, including tapped-delay line transversal filters with multigigahertz bandwidths and time-bandwidth products as large as 30, and narrowband (less than 3% bandwidth) microstrip filters.