Before the emergence of ultra-wideband (UWB) radios, widely used wireless communications were based on sinusoidal carriers, and impulse technologies were employed only in specific applications (e.g. radar). In 2002, the Federal Communication Commission (FCC) allowed unlicensed operation between 3.1–10.6 GHz for UWB communication, using a wideband signal format with a low EIRP level (−41.3dBm/MHz). UWB communication systems then emerged as an alternative to narrowband systems and significant effort in this area has been invested at the regulatory, commercial, and research levels.

IEEE Transactions on Microwave Theory and Techniques and Antennas and Propagation Announce a Joint Special Issue on Ultra-Wideband (UWB) Technology

Aspects of the subject disclosure may include, for example, receiving, by a feed point of a dielectric antenna, electromagnetic waves from a dielectric core coupled to the feed point without an electrical return path, where at least a portion of the dielectric antenna comprises a conductive surface, directing, by the feed point, the electromagnetic waves to a proximal portion of the dielectric antenna, and radiating, via an aperture of the dielectric antenna, a wireless signal responsive to the electromagnetic waves being received at the aperture. Other embodiments are disclosed.

Method and apparatus for coupling an antenna to a device

Substrate integrated waveguide (SIW) technology provides an attractive solution to the integration of planar and nonplanar circuits by using a planar circuit fabrication process. However, it is usually difficult to implement the negative coupling structure required for the design of compact canonical folded elliptic or quasi-elliptic cross-coupled bandpass filter on the basis of a single-layer SIW. In this paper, a special planar negative coupling scheme including a magnetic coupling post-wall iris and a balanced microstrip line with a pair of metallic via-holes is studied in detail. Two -band fourth-degree cross-coupled bandpass filters without and with source-load coupling using the negative coupling structures are then proposed and designed. The two novel SIW filters having the same center frequency of 20.5 GHz and respective passband width of 700 and 800 MHz are implemented on a single-layer Rogers RT/Duroid 5880 substrate with thickness of 0.508 mm. Measured results of those filters, which exhibit a high selectivity, and a minimum in-band insertion loss of approximately 0.9 and 1.0 dB, respectively, agree well with simulated results.

Substrate Integrated Waveguide Cross-Coupled Filter With Negative Coupling Structure

A distributed antenna and backhaul system provide network connectivity for a small cell deployment. Rather than building new structures, and installing additional fiber and cable, embodiments described herein disclose using high-bandwidth, millimeter-wave communications and existing power line infrastructure. Above ground backhaul connections via power lines and line-of-sight millimeter-wave band signals as well as underground backhaul connections via buried electrical conduits can provide connectivity to the distributed base stations. An overhead millimeter-wave system can also be used to provide backhaul connectivity. Modules can be placed onto existing infrastructure, such as streetlights and utility poles, and the modules can contain base stations and antennas to transmit the millimeter-waves to and from other modules.

Backhaul link for distributed antenna system

A distributed antenna system is provided that frequency shifts the output of one or more microcells to a 60 GHz or higher frequency range for transmission to a set of distributed antennas. The cellular band outputs of these microcell base station devices are used to modulate a 60 GHz (or higher) carrier wave, yielding a group of subcarriers on the 60 GHz carrier wave. This group will then be transmitted in the air via analog microwave RF unit, after which it can be repeated or radiated to the surrounding area. The repeaters amplify the signal and resend it on the air again toward the next repeater. In places where a microcell is required, the 60 GHz signal is shifted in frequency back to its original frequency (e.g., the 1.9 GHz cellular band) and radiated locally to nearby mobile devices.

Remote distributed antenna system

The invention relates to a polarization separating filter which can be integrated in a planar hollow conductor circuit and which is comprised of a central hollow conductor (1) in which two waves that are polarized in an orthogonally linear manner are capable of being propagated. One end of the central hollow conductor (1) is terminated by a short-circuit wall (2), and two hollow conductors (3, 4) are, in the vicinity of the short-circuit wall (2), coupled to two opposing walls of the central hollow conductor (1) in an at least approximately identical cross-sectional plane that extends perpendicular to the longitudinal axis of the hollow conductor. The hollow conductors (3, 4) coupled on the faces thereof to the central hollow conductor (1) are turned with regard to their cross-sections in such a manner that the fields therein are oriented orthogonally in relation to one another.

Polarization separating filter

A reconfigurable OMUX solution is introduced that allows flexible re-allocation of channels including contiguous/non-contiguous ones with variable center frequencies and bandwidths. Re-configurable high Q filters and compensation circuits are directly coupled to a manifold. The novel filter designs are capable to provide remote controlled bandwidth and center frequency tuning of the channel responses with only two actuation drives. The compensation circuits are adapting the adjacent channel impedances when replacing contiguous channels, to avoid complex retuning needs for the channel filters. A two channel OMUX design at 11GHz with one fixed channel filter, one reconfigurable filter and compensation circuits is introduced to prove the general solution. The EM analyses results for the different settings, including contiguous/non-contiguous channels with variable center frequencies and bandwidths demonstrate the feasibility of reconfigurable OMUX implementations with state-of-the-art technologies.

OMUX approach providing re-configuration of contiguous/non-contiguous channel allocations with variable frequencies and bandwidths

The paper presents novel coupling schemes for microwave resonator filters. Some of these solutions contain more than one main path between the input and output. These paths may be interacting or non-interacting. In other solutions, only some of the direct (main) couplings are zero. It is shown that higher-order filter characteristics can be obtained from lower- order sections, which are connected in parallel between the source and the load, by proper superposition of the individual lower- order responses. Possible applications of these solution to actual design problems are discussed. Index Terms-resonator filters, elliptic filters, band-pass filters, synthesis, N-path filters, design, dual-mode filters. I. ~

Novel Coupling Schemes for Microwave

This paper presents guidelines for the design of dual-band transformers in both rectangular and ridge waveguide technologies. Four to eight transformer sections are used to satisfy specifications for advanced satellite and terrestrial communications in C-band and Ku-band. Compact designs are obtained by synthesis of wideband components, which are then optimized for dual-band application. Measurements of a Ku-band prototype verify the design approach

/pdf/design-of-dual-band-waveguide-transformers-yh18o3whsl.pdf

Design of dual-band waveguide transformers

A novel twist solution is introduced providing high performance matching of two waveguides interfaces with an angular offset. It is based on a central angular step for the complete offset rotation in combination with double ridge waveguide transformer sections towards the waveguide interfaces1. The transformer waveguide cross sections are directly fitting with the interface waveguides which accommodates with easy and low cost manufacturing in one piece by standard CNC milling techniques. It also facilitates integration and assembly issues within overall waveguide systems. It is shown that this approach provides high performance properties over more than 40% bandwidth for angular offsets up to 70 degree. A twist design at 28GHz has been realized to demonstrate the feasibility of the concept. To accommodate with the specific matching of two waveguides with perpendicular alignment, the approach has to be altered, i.e., the ridges of the transformer sections have to be considered with an appropriate offset from the center locations.

Uwe Rosenberg

Papers

Polarization separating filter

OMUX approach providing re-configuration of contiguous/non-contiguous channel allocations with variable frequencies and bandwidths

Novel Coupling Schemes for Microwave

Design of dual-band waveguide transformers

Compact waveguide twist design fitting with interfacing waveguide cross sections