8,561 research outputs found
On the Frequency Dependency of Radio Channel's Delay Spread: Analyses and Findings From mmMAGIC Multi-frequency Channel Sounding
This paper analyzes the frequency dependency of the radio propagation
channel's root mean square (rms) delay spread (DS), based on the
multi-frequency measurement campaigns in the mmMAGIC project. The campaigns
cover indoor, outdoor, and outdoor-to-indoor (O2I) scenarios and a wide
frequency range from 2 to 86 GHz. Several requirements have been identified
that define the parameters which need to be aligned in order to make a
reasonable comparison among the different channel sounders employed for this
study. A new modelling approach enabling the evaluation of the statistical
significance of the model parameters from different measurements and the
establishment of a unified model is proposed. After careful analysis, the
conclusion is that any frequency trend of the DS is small considering its
confidence intervals. There is statistically significant difference from the
3GPP New Radio (NR) model TR 38.901, except for the O2I scenario.Comment: This paper has been accepted to the 2018 12th European Conference on
Antennas and Propagation (EuCAP), London, UK, April 201
28 GHz and 73 GHz Millimeter-Wave Indoor Propagation Measurements and Path Loss Models
This paper presents 28 GHz and 73 GHz millimeter- wave propagation
measurements performed in a typical office environment using a 400
Megachip-per-second broadband sliding correlator channel sounder and highly
directional steerable 15 dBi (30 degrees beamwidth) and 20 dBi (15 degrees
beamwidth) horn antennas. Power delay profiles were acquired for 48
transmitter-receiver location combinations over distances ranging from 3.9 m to
45.9 m with maximum transmit powers of 24 dBm and 12.3 dBm at 28 GHz and 73
GHz, respectively. Directional and omnidirectional path loss models and RMS
delay spread statistics are presented for line-of-sight and non-line-of-sight
environments for both co- and cross-polarized antenna configurations. The LOS
omnidirectional path loss exponents were 1.1 and 1.3 at 28 GHz and 73 GHz, and
2.7 and 3.2 in NLOS at 28 GHz and 73 GHz, respectively, for
vertically-polarized antennas. The mean directional RMS delay spreads were 18.4
ns and 13.3 ns, with maximum values of 193 ns and 288 ns at 28 GHz and 73 GHz,
respectively.Comment: 7 pages, 9 figures, 2015 IEEE International Conference on
Communications (ICC), ICC Workshop
Outdoor to Indoor Penetration Loss at 28 GHz for Fixed Wireless Access
This paper present the results from a 28 GHz channel sounding campaign
performed to investigate the effects of outdoor to indoor penetration on the
wireless propagation channel characteristics for an urban microcell in a fixed
wireless access scenario. The measurements are performed with a real-time
channel sounder, which can measure path loss up to 169 dB, and equipped with
phased array antennas that allows electrical beam steering for directionally
resolved measurements in dynamic environments. Thanks to the short measurement
time and the excellent phase stability of the system, we obtain both
directional and omnidirectional channel power delay profiles without any delay
uncertainty. For outdoor and indoor receiver locations, we compare path loss,
delay spreads and angular spreads obtained for two different types of
buildings
Indoor wireless communications and applications
Chapter 3 addresses challenges in radio link and system design in indoor scenarios. Given the fact that most human activities take place in indoor environments, the need for supporting ubiquitous indoor data connectivity and location/tracking service becomes even more important than in the previous decades. Specific technical challenges addressed in this section are(i), modelling complex indoor radio channels for effective antenna deployment, (ii), potential of millimeter-wave (mm-wave) radios for supporting higher data rates, and (iii), feasible indoor localisation and tracking techniques, which are summarised in three dedicated sections of this chapter
Comprehensive design and propagation study of a compact dual band antenna for healthcare applications
In this paper, a dual band planar inverted F antenna (PIFA) has been investigated for cooperative on- and off-body communications. Free space and on-body performance parameters like return loss, bandwidth, radiation pattern and efficiency of this antenna are shown and investigated. The on- and off-body radio propagation channel performance at 2.45 GHz and 1.9 GHz have been investigated, respectively. Experimental investigations are performed both in the anechoic chamber and in an indoor environment. The path loss exponent has been extracted for both on- and off-body radio propagation scenarios. For on-body propagation, the path loss exponent is 2.48 and 2.22 in the anechoic chamber and indoor environment, respectively. The path loss exponent is 1.27 for off-body radio propagation situation. For on-body case, the path loss has been characterized for ten different locations on the body at 2.45 GHz, whereas for off-body case radio channel studies are performed for five different locations at 1.9 GHz. The proposed antenna shows a good on- and off-body radio channel performance
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