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Wireless systems have become more and more advanced in terms of handling the statistical properties of wireless channels. For example, the 4G long term evolution (LTE) system takes advantage of multiport antennas [multiple-input multiple-output (MIMO) technology] and orthogonal frequency division multiplexing (OFDM) to improve the detection probability of single bitstream by diversity in the spatial and frequency domains, respectively. The 4G system also supports transmission of two bitstreams by appropriate signal processing of the MIMO subchannels. The reverberation chamber emulates according to previous works rich isotropic multipath (RIMP) and has proven to be very useful for characterizing smart phones for LTE systems. The measured throughput can be accurately modeled by the simple digital threshold receiver, accounting accurately for both the MIMO and OFDM functions. The throughput is equivalent to the probability of detection (PoD) of the transmitted bitstream. The purpose of this paper is to introduce a systematic approach to include the statistical properties of the user and his or her terminal, when characterizing the performance. The user statistics will have a larger effect in environments with stronger line-of-sight (LOS), because the angle of arrival and the polarization of the LOS contribution vary due to the user's orientation and practices. These variations are stochastic, and therefore, we introduce the term random-LOS to describe this. This paper elaborates on the characterization of an example antenna in both RIMP and random-LOS. The chosen antenna is a wideband microbase transceiver station (BTS) antenna. We show how to characterize the micro-BTS by the PoD of one and two bitstreams in both RIMP and random-LOS, by considering the user randomly located and oriented within the angular coverage sector. We limit the treatment to a wall-mounted BTS antenna, and assume a desired hemispherical coverage. The angular coverages of both one and two bitstreams for the random-LOS case are plotted as MIMO-coverage radiation patterns of the whole four-port digital antenna system. Such characterizations in terms of PoD have never been done before on any practical antenna system. The final results are easy to interpret, and they open up a new world of opportunities for designing and optimizing 5G antennas on system level.INDEX TERMS Micro base transceiver station (uBTS), rich isotropic multipath (RIMP), probability of detection (PoD), random line-of-sight (random-LOS).

The drying of grain in dryers of a crossflow moving bed type was theoretically and excerimentally studied. Two different duer configurations were analyzed. a drver Gith centrdkr distribution and another wilh multl'ole air ducts. ~xoenmental in~ormallun was obtained in p~lot-size dryers A mathem;ticnl model lo rikulalc llx process was developed Hindered drylng u;l\ accounrerl lor by uslng the conccpl of relative drvine rate.-~n adiustable fact06 s~ecific to the drver8. wasised to account for the un~er(~>nt~es of the>ontacl area nnd'the umsfer c&ffic~ents mcountercd in the literature. Agreement between ex~rimental rcsulls and simul.!lions WL. farly eood. Simulatiins showed that distance between inlet air and outlet devices. air to -solid flow ratlo and dryer height to crurs seclion muo havc great ~nflucnce on the process The mathematicd model may be a uceful tool for process explor~tion and optimization of this type of dryers INTRODUCTION

Abstract:In the European Union's Energy Performance of Buildings Directive, the energy efficiency goal for buildings is set in terms of primary energy use. In the proposal from the National Board of Housing, Building, and Planning, for nearly zero energy buildings in Sweden, the use of primary energy is expressed as a primary energy number calculated with given primary energy factors. In this article, a multi-dwelling building is simulated and the difference in the primary energy number is investigated when the building uses heat from district heating systems or from heat pumps, alone or combined with solar thermal or solar photovoltaic systems. It is also investigated how the global CO 2 emissions are influenced by the different energy system combinations and with different fuels used. It is concluded that the calculated primary energy number is lower for heat pump systems, but the global CO 2 emissions are lowest when district heating uses mostly biofuels and is combined with solar PV systems. The difference is up to 140 tonnes/year. If the aim with the Swedish building code is to decrease the global CO 2 emissions then the ratio between the primary energy factors for electricity and heat should be larger than three and considerably higher than today.