Providing reliable low latency wireless links for advanced manufacturing and processing systems is a vision of Industry 4.0. Developing, testing and rating requires accurate models of the radio propagation channel. The current 3rd generation partnership project (3GPP) new radio (NR) model as well as the quasi deterministic radio channel generator (QuaDRiGa) lack the propagation parameters for the industrial indoor scenario. To close this gap, measurements were conducted at 2.37 GHz and 5.4 GHz at operational Siemens premises in Nuremberg, Germany. Furthermore, the campaign was planned to allow the test and parameterization of new features of the QuaDRiGa channel model such as support for device-to-device (D2D) radio links and spatial consistency. A total of 5.9 km measurement track was used to extract the statistical model parameters for line of sight (LOS) and Non-LOS propagation conditions. It was found that the metallic walls and objects in the halls create a rich scattering environment, where a large number of multipath components arrive at the receiver from all directions. This leads to a robust communication link, provided that the transceivers can handle the interference. The extracted parameters can be used in geometric-stochastic channel models such as QuaDRiGa to support simulation studies, both on link and system level.

In this paper, we present the channel measurement results of vehicle-to-vehicle (V2V) measurement campaign carried out in Oulu city center, Finland. The measurements were conducted with EB Propsound CSTMat 2.3 GHz and 5.25 GHz center frequencies. The antennas were installed on the roof of the vehicles and the measurements were performed for single-input multiple-output (SIMO) antenna configuration. The campaign results are presented in the form of path loss, delay spread (DS), maximum excess delay, the standard deviation of slow fading (SF) and K-factor. Furthermore, we propose the method for calculating correlation distance for large scale parameters in V2V channel and present the results for correlation distances of SF, DS and K-factor. The correlation distances less than 11 meters were observed.

This paper studies in-band interference of different kind of ultra wideband (UWB) signals. UWB frequency spectra are produced by using several types of narrow pulse waveforms, all based on the Gaussian pulse. Due to the extremely wide bandwidth, these signals spread over the frequency bands allocated to other radio systems. In-band interference power is calculated over the IF bandwidths of two victim receivers as a function of pulse width. Also, the signal attenuation with distance is presented. The victim systems under the study are GPS (L1-band) and GSM900. Based on the results, the 3/sup rd/ derivative of a Gaussian pulse seems to be the best choice, from the interference point of view, among the waveforms included in this study. It causes less interference than the Gaussian pulse or Gaussian doublet if the pulse widths are shorter than 1 ns. The system utilizing the direct sequence concept caused less in-band interference power than the system utilizing time hopping amongst all waveforms studied. The studied UWB systems are based on bi-phase baseband data modulation.

This paper evaluates the level of interference caused by different ultra-wideband (UWB) signals to other various radio systems, as well as the performance degradation of UWB systems in the presence of narrowband interference and pulsed jamming. The in-band interference caused by a selection of UWB signals is calculated at GSM900, UMTS/wideband code-division multiple-access (WCDMA), and Global Position System (GPS) frequency bands as a function of the UWB pulsewidth. Several short-pulse waveforms, based on the Gaussian pulse, can be used to generate UWB transmission. The two UWB system concepts studied here are time hopping and direct sequence spread spectrum. Baseband binary pulse amplitude modulation is used as the data modulation scheme. Proper selection of pulse waveform and pulsewidth allows one to avoid some rejected frequency bands up to a certain limit. However, the pulse shape is also intertwined with the data rate demands. If short-pulses are used in UWB communication the high-pass filtered waveforms are preferred according to the results. The use of long pulses, however, favors the generic Gaussian waveform instead. An UWB system suffers most from narrowband systems if the narrowband interference and the nominal center frequency of the UWB signal overlap. This is proved by bit-error rate simulations in an additive white Gaussian noise (AWGN) channel with interference at global system for mobile communication (GSM) and UMTS/WCDMA frequencies.

This paper explains the realization and the performance of a digital stepping correlator in a wideband radio channel measurement system. Radio channel sounding is based on the estimation of the radio channel by use of maximum length sequence (m-sequence) as an effective sounding signal. Signal is detected using the stepping correlator receiver. The received signal is not converted to the baseband but the sampling is done direct from the IF-frequency. Digital implementation gives also a possibility to use a windowing property when those parts of the impulse responses that do not contain signal power are abandoned during measurements. The windowing enables high radio channel sampling rates.

The multipath characteristics of the wireless local loop (WLL) channel were studied over both short and long time periods in urban and sub-urban high-rise and small-house environments. Wideband measurements were performed at a centre frequency of 1.3 GHz with a sliding correlation measurement system using a chip rate of 15 MHz. The receiver was situated at regular cellular base stations, and the transmitter with an omnidirectional antenna was moved to several rooms in different buildings around the base station sites. During the recordings the movement of people in the measurement rooms was restricted. The short-term results show a high degree of similarity in the multipath characteristics of the WLL channel in urban and sub-urban high-rise environments. The maximum measured values of delay spreads for the urban and suburban high-rise environments were 410 ns and 360 ns, respectively. For the sub-urban small-house environment the data indicate lower values of delay spread. The channel was shown to be very slowly fading, being in most situations essentially static over short time periods of the order of several tens of seconds. The variation of the channel characteristics over long time periods was shown to be significant.