Channel Characteristics of MIMO-WLAN Communications at 60GHz for Various Corridors

[[abstract]]A comparison of 4 × 4 multiple-input multiple-output wireless local area network wireless communication characteristics for six different geometrical shapes is investigated. These six shapes include the straight shape corridor with rectangular cross section, the straight shape corridor with arched cross section, the curved shape corridor with rectangular cross section, the curved shape corridor with arched cross section, the L-shape corridor, and the T-shape corridor. The impulse responses of these corridors are computed by applying shooting and bouncing ray/image (SBR/Image) techniques along with inverse Fourier transform. By using the impulse response of these multipath channels, the mean excess delay, root mean square (RMS) delay spread for these six corridors can be obtained. Numerical results show that the capacity for the rectangular cross section corridors is smaller than those for the arched cross section corridors regardless of the shapes. And the RMS delay spreads for the T-and the L-shape corridors are greater than the other corridors.[[notice]]補正完畢[[incitationindex]]SCI[[incitationindex]]EI[[booktype]]紙本[[booktype]]電子

The road to 100 Gb/s wireless and beyond : basic issues and key directions

This work addresses the blueprint of short-range wireless systems supporting data rates of 100 Gb/s and beyond. A number of usage models are identified for such ultra-high data rates, including wireless communication within electronic equipment enabling possibilities such as wireless reconfigurable chip-to-chip communication. The 300 GHz band spanning about 55 GHz of contiguous bandwidth is identified as the most suitable candidate to accommodate these bandwidth-demanding applications. Furthermore, the main bottleneck issues are discussed: power consumption and antenna integration. With the help of basic link budget considerations, we indicate the technical feasibility of the proposed concept with compact low-cost antenna solutions. Finally, we discuss the overall system architecture to be standardized and indicate a number of key research topics

Analysis of human skin tissue by millimeter-wave reflectometry

Background/pupose: Millimeter-wave reflectometry is a potentially interesting technique to analyze the human skin in vivo in order to determine the water content locally in the skin. Purpose of this work is to investigate the possibility of skin-tissue differentiation. In addition, it addresses the influence of the pressure of the probe on the skin, the influence of an airgap between probe and skin as well as the influence of a bandage between probe and skin. Methodology: Reflection coefficients at various positions on the skin are measured in the 40 – 60 GHz range and the examined effects are quantified in terms of magnitude and phase of the reflection coefficient. Also the possibility to perform tissue differentiation is quantified. Results: It is indicated that differentiation of skin tissue can be performed on the basis of the magnitude of the reflection coefficient provided that no air-gap exists between probe and skin. The influence of probe pressure can be substantial in particular for phase measurements. The presence of an airgap between probe and skin reduces the differentiation capability of the considered measurement technique, whereas a bandage between probe and skin did not significantly affect the differentiation power. Conclusion: The results of this work confirm the potential of millimeter-wave reflectometry for determination of water content in skin tissue which may lead to interesting applications as early detection of skin cancer and through-bandage monitoring of wounds

Impact of regulations on feasible distance between 60 GHz devices

In this paper we address the impact of the current world-wide safety and interference regulations with respect to the 60 GHz band on the feasible distance between a transmitting and a receiving device assuming a beam-forming array antenna at both ends of the link. From these considerations it occurs that these regulations impose severe constraints in terms of allowable antenna gain at the transmitter as well as allowable levels of transmit power in case of non-line-of-sight operation. Therefore, these regulatory constraints necessitate an additional amount of beam-focusing at the receiving end. The feasible separation distance is determined assuming a balanced distribution of antenna gain between transmit antenna and receive antenna and technically well-feasible levels of transmit power. Furthermore, the propagation conditions that typically occur in the 60 GHz band are taken into account as well as the relevant user and system requirements as formulated in current design and standardization documents

60 GHz radio : prospects and future directions

This paper addresses the basic issues regarding the design and development of wireless systems that will operate in the 60 GHz band. The 60 GHz band is of much interest since this is the band in which a massive amount of spectral space (5 to 7 GHz) has been allocated for dense wireless local communications

Wide-band measurements of Mm-wave indoor radio channels

\u3cp\u3eThe results of wide-band measurements of indoor radio channels operating in a 2 GHz frequency band centered around 58 GHz are presented. The measurements were performed with a frequency step sounding technique. From the resulting frequency domain data base, cell coverage and time delay spread with both line-of-sight and obstruction of the direct path are derived. Eight indoor environments were subjected to propagation experiments. Since these areas are well defined and described the results can be readily related to other environments.\u3c/p\u3