A wideband 3-dB coupler using substrate integrated gap waveguide (SIGW) is proposed based on the principle of the branch-line coupler structure. The SIGW coupler design is comprehensively studied. It is found that SIGW conducting ridge vias play a significant role and have a strong impact on the cavity resonance, passband, and impedance matching. A prototype of the proposed SIGW coupler is fabricated and tested, and the measured agrees well with the simulated. The coupler, better than the reported, has a passband of ~5 GHz from 23.59 to 29 GHz with the isolation above 20 dB, covering the 24.25–27.5-GHz and 27.5–28.5-GHz frequency bands of 5G.

A Substrate Integrated Gap Waveguide Based Wideband 3-dB Coupler for 5G Applications

A silicon substrate integrated optical mode data exchanger comprises a first microring resonator and a second microring resonator, wherein the first microring resonator is composed of a ring waveguide and a bending waveguide, and the second microring resonator is composed of another ring waveguide and two straight waveguides. A traditional wavelength division multiplexing wavelength switching function is introduced into a model reuse system by means of a relatively simple structure, and faster application of the model reuse technique to the optical communication field is promoted. In terms of device manufacturing, the device is completely compatible with an existing mature CMOS technology, so that the device is small in size and easy to integrate; meanwhile, due to the high speed and low power consumption, the data exchanger has great application prospects in the aspects of optical communication and photon calculation.

Silicon substrate integrated optical mode data exchanger

This paper offers an approximate, but very convenient and accurate, manner to find the desired strip width for substrate integrated gap waveguide (SIGW) with a given characteristic impedance and the conductor and dielectric attenuation constants, without any complicated manual calculations or time-consuming full-wave simulation and optimization iterations. Moreover, the investigation of the transition between SIGW and microstrip lines will prove that an additional transition structure, such as a conventional microstrip taper, is not required any more at millimeter-wave frequencies for the desired transmission performance. This is a useful feature in circuit design and compactness. Both of the above works will be of great help to realize future feeding networks for SIGW antenna arrays or other types of cost-effective SIGW passive components at high frequencies. Two SIGW prototypes, working at Ka and V bands, are fabricated and offer experimental verifications, which present good agreement with the simulation results.

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Design of Substrate Integrated Gap Waveguide and Their Transitions to Microstrip Line, for Millimeter-Wave Applications

The invention relates to an MIMO antenna with low cross coupling four-unit UWB and belongs to the technical field of wireless communication The MIMO antenna with low cross coupling four-unit UWB comprises a dielectric slab, four monopole UWB antenna-units and two butterfly-shaped planar EBG structural square matrixes, wherein the 4 antenna units are respectively located on four point angles of the dielectric slab, and are mutually perpendicular to each other, with the entirety being centrosymmetric relative to the centre of the dielectric slab Furthermore, the EBG structural square matrixes are made up of the new type butterfly sized planar EBG and adopts 6x6 matrix-arranged pattern, respectively on the centre of the front and back sides of the dielectric slab MIMO antenna with low cross coupling four-unit UWB has the advantages of wide broadband, low cross coupling, simple structure, and is easy to make and integrate and the like, thereby applying to all kinds of minitype mobile terminals

MIMO antenna with low cross coupling four-unit UWB

We propose and fabricate a polymeric thermo-optic mode switch based on a Mach-Zehnder interferometer (MZI) by connecting two asymmetric directional couplers formed with a single-mode waveguide (SMW) and a two-mode waveguide (TMW). Thin-film heaters were deposited on the arms of the MZI to realize the switching function. The LP01 mode in the SMW and the LP11a mode in the TMW can be converted to each other by driving the voltage supplied to the heater. Our typical fabricated device with polymer material shows extinction ratios higher than ~11 dB in the C-band. The switching power measured at 1550 nm is lower than 10 mW and the switching rise time and fall time are $540.0~\mu \text{s}$ and $440.0~\mu \text{s}$ , respectively. The device could find applications in reconfigurable mode-division-multiplexing systems.

Polymeric Waveguide MZI Thermo-Optic Mode Switch Based on Asymmetric Directional Coupler

In this paper., a seventh-order filter using substrate integrated gap waveguide (SIGW) technology., i.e. SIGW filter., is proposed for the first time., which has high selectivity and wide stopband. The SIGW filter includes three-layer substrates. The top layer substrate realizes a perfect magnetic conductor (PMC) using periodic plated vias and metallic patches. It is applied for packaging substrate integrated waveguide (SIW) filter to avoid interference and losses induced by external radiation emission and internal radiation leakage. The middle layer substrate generates a gap layer. In the base/bottom layer, cascaded resonators of the SIW filters are formed by properly etching slots on the metal plane and placing plated vias in the middle of this layer. The higher-order modes of TE 103 and TE104 are suppressed using slots designed in the base layer at the third-order cavity, which leads to wide stopband. Moreover, the effect of the SIGW-based PMC structure on bandwidth and transmission zeroes is studied. The measured results demonstrate that the proposed SIGW filters perform well in the both passband and stopband.

Substrate Integrated Gap Waveguide Bandpass Filters with High Selectivity and Wide Stopband

The invention relates to a triple-frequency-band antenna used in WLAN and WiMAX and belongs to the technical field of wireless communication. The triple-frequency-band antenna comprises a bottom first microstrip branch structure (1), a left second microstrip branch structure (2, 3), an intermediate microstrip branch structure (4), a right fourth microstrip branch structure (5-7), a microstrip feed line (8), a comb-shaped parasitic unit (9-12), a common-ground structure (13-18), and a dielectric slab (19). The triple-frequency-band antenna is characterized in that (a), a basic radiation unit is formed by the four microstrip branch structures mentioned above and is directly connected with the microstrip feed line (8); (b), a gap is arranged between the microstrip feed line (8) and the common-ground structure such that coplanar waveguide feed is formed; and (c), the dielectric slab uses FR4 dielectric material. The triple-frequency-band antenna has advantages of compact structure, easy integration, simple processing, multiple frequency bands, good tenability, and a stable directional diagram, and may simultaneously satisfy requirements of WLAN and WiMAX systems.

Triple-frequency-band antenna used in WLAN and WiMAX

A novel optical waveguide LP01/LP02 mode converter

An ultra-wideband bandpass (UWB) filter using integrated substrate gap waveguide (ISGW) technology is proposed, which has ultra-wideband and high selectivity. The UWB ISGW bandpass filter structure consists of three layer dielectric substrates, the top substrate uses metallic via-holes and metallic patches to implement perfect magnetic conductor (PMC) structure, which is suitable for packaging substrate integrated waveguide (SIW) filters to avoid external interference and loss caused by radiation and internal radiation leakage, the middle layer substrate provides a stable gap layer, and the base substrate is used to obtain a SIW filter by etching the slots in the metal plane and placing metallic via-holes in the middle of the layer, i.e. a self-packaged UWB ISGW filter. The proposed filter was fabricated and tested at a center frequency of 17.5 GHz as an example. The measurements show that the filter has a passband from 14.4 to 20.7 GHz, i.e. This filter has a fractional bandwidth (FBW) of 36%, and an insertion loss of 0.91 dB. More importantly, thanks to ISGW, two transmission zeros are obtained at 12.9 and 22.1 GHz to improve high selectivity.

A Self-Packaged Ultra-Wide Band Bandpass Filter Using Integrated Substrate Gap Waveguide

The invention relates to a small-sized coplanar waveguide fed ultra-wide band antenna, and belongs to the technical filed of wireless communication. The small-sized coplanar waveguide fed ultra-wide band antenna comprises a rectangular FR4 dielectric slab with the dielectric constant being 4.6, a first step-type microstrip structure, a second step-type microstrip structure, a double-arch-bridge type microstrip structure, a moon-shaped microstrip structure, a rectangular microstrip structure, a rectangular microstrip feedline, a first arc-slope-shaped microstrip structure and a second arc-slope-shaped microstrip structure, wherein the first step-type microstrip structure, the second step-type microstrip structure, the double-arch-bridge type microstrip structure, the moon-shaped microstrip structure and the rectangular microstrip structure form a radiation sticker with a small semi-circular groove, a big semi-circular groove and a rectangular groove; the first arc-slope-shaped microstrip structure and the second first arc-slope-shaped microstrip structure form a common ground structure; a gap is formed between the first arc-slope-shaped microstrip structure and the rectangular microstrip feedline as well as between the second arc-slope-shaped microstrip structure and the rectangular microstrip feedline, so that coplanar waveguide is formed. The small-sized coplanar waveguide fed ultra-wide band antenna provided by the invention is simple in structure, compact in size, low in cost, high in precision, wide in frequency band, good in radiation characteristic, easy to integrate and suitable for small and portable ultra wide band terminal equipment.

Yuan Hong

Papers

Substrate Integrated Gap Waveguide Bandpass Filters with High Selectivity and Wide Stopband

Triple-frequency-band antenna used in WLAN and WiMAX

A novel optical waveguide LP01/LP02 mode converter

A Self-Packaged Ultra-Wide Band Bandpass Filter Using Integrated Substrate Gap Waveguide

Small-sized coplanar waveguide fed ultra-wide band antenna