Abstract
The aim of this article is to present a simple but robust model characterizing the frequency dependent transfer function of an in-vehicle ultra-wide-band channel. A large number of transfer functions spanning the ultra-wide-band (3 GHz to 11 GHz) are recorded inside the passenger compartment of a four seated sedan car. It is found that the complex transfer function can be decomposed into two terms, the first one being a real valued long term trend that characterizes frequency dependency with a power law, and the second term forms a complex correlative discrete series which may be represented via an autoregressive model. An exhaustive simulation framework is laid out based on empirical equations characterizing trend parameters and autoregressive process coefficients. The simulation of the transfer function is straightforward as it involves only a handful of variables, yet it is in good agreement with the actual measured data. The proposed model is further validated by comparing different channel parameters, such as coherence bandwidth, power delay profile, and root mean square delay spread, obtained from the raw and the synthetic data sets.
bibTeX Reference
@ARTICLE{24_CHANDRA2016_IEEE_TVT,
author = {CHANDRA, Aniruddha and PROKES, Ales and MIKULASEK, Tomas and BLUMENSTEIN,
Jiri and KUKOLEV, Pavel and ZEMEN, Thomas and MECKLENBRAUKER, Christoph},
title = {Frequency-domain in-vehicle UWB channel modelling},
journal = {IEEE Transactions on Vehicular Technology},
year = {2016},
volume = {65},
pages = {3929–3940},
number = {6},
issn = {0018-9545}
}

Abstract
The paper provides real-word wireless measurement data of the intra-vehicular channel for both the 3-11 GHz and the 55-65 GHz frequency band under similar conditions. By spatially averaging channel impulse response (CIR) realizations within a10×10 grid, we obtain the power-delay profile (PDP). The data measured at 3-11 GHz and 55-65 GHz exhibit significant differences in terms of root mean square (RMS) delay spread, number of resolvable clusters and variance of the maximal excess delay. Moreover, we evaluate the spatial stationarity via the Pearson correlation coefficient and via the PDP collinearity depending on the distance in the grid. The measured and calculated results indicate that a strong reverberation inside the vehicle produces similar PDPs within the range of approximately 10 wavelengths. We also provide a linear piecewise model of the PDP in logarithmic scale and a generalized extreme value (GEV) model of small-scale signal fading. Our channel model is validated utilizing the Kolmogorov-Smirnov (K-S) test.
bibTeX Reference
@ARTICLE{25_BLUMENSTEIN2016_IEEE_TVT,
author = {BLUMENSTEIN, Jiri and PROKES, Ales and CHANDRA, Aniruddha and MIKULASEK,
Tomas and MARSALEK, Roman and ZEMEN, Thomas and MECKLENBRAUKER, Christoph},
title = {In-Vehicle Channel Measurement, Characterization and Spatial Consistency
Comparison of 3-11 GHz and 55- 65 GHz Frequency Bands},
journal = {IEEE Transactions on Vehicular Technology},
year = {2016},
volume = {PP},
pages = {1–13},
number = {99},
doi = {10.1109/TVT.2016.2600101}
}

Abstract
The randomness in UWB channel for small positional variations around a car, parked in an underground garage, is reported. Keeping the receiver fixed at the conventional rooftop antenna location, the transmitter location is changed to study the variations against distance, angle, and height. The path loss is found to be monotonically increasing with distance but varies randomly with angle and height and thereby renders signal strength based ranging inaccurate for such scenarios. On the other hand, the first peak can reliably provide distance estimate irrespective of transmitter angle or height. The number of clusters in the delay profile reduces with distance but the shape of the profile remains fairly consistent across angle. The Saleh-Valenzuela parameter values also vary with distance and height but their average values are close to IEEE 802.15.3 standard.
bibTeX Reference
@ARTICLE{26_CHANDRA2016_IEEE_AWPL,
author = {CHANDRA, Aniruddha and KUKOLEV, Pavel and MIKULASEK, Tomas and PROKES,
Ales and MECKLENBRAUKER, Christoph},
title = {UWB measurements for spatial variability and ranging: Parked car
in underground garage},
journal = {IEEE Antennas and Wireless Propagation Letters},
year = {2016},
volume = {PP},
doi = {10.1109/LAWP.2016.2628390}
}

Abstract
First results for frequency-domain channel measurements in a bus in the 60 GHz millimeter wave band are reported. The simple setup used consists of analog signal generator and scalar signal analyzer, instead of vector network analyzers which are costly and suffer from cable length limitation. Path loss values are computed directly from the frequency-domain data and log-distance model parameters are extracted. Next, assuming minimum phase channel, delay profiles are constructed from amplitude-only data following a Hilbert transform. Using the path loss and delay parameter values, the effect of seat position, passenger occupancy, reflections from glass window etc. are discussed in detail.
bibTeX Reference
@ARTICLE{27_CHANDRA2016_MIS,
author = {CHANDRA, Aniruddha and PROKES, Ales},
title = {Millimeter-wave channel characteristics inside bus: Field experiment
results},
journal = {Mobile Information Systems},
year = {2016},
note = {Resubmitted}
}

Abstract
In this work, antennas utilized for an intra-vehicle 3–11GHz and 55–65GHz channel measurement are described. A measurement antenna should not only provide a wide-band impedance bandwidth but also have a stable radiation pattern and a high fidelity factor. For the lower frequency band, a metal conical monopole antenna is proposed for its frequency stable H-plane omnidirectional radiation pattern. An open waveguide antenna (OWGA) and a substrate integrated waveguide slot antenna array are discussed for 55–65GHz channel measurement. In the case of the OWGA, the effect of a flange on antenna properties is investigated. The suitability of these antennas for time domain measurement is discussed using fidelity factor. Both simulated and measured properties of the antennas are presented. The proposed antennas are also suitable for out-of-vehicle channel measurement. Most information about the channel measurement are freely available online: http://www.radio.feec.vutbr.cz/GACR-13-38735S/.
bibTeX Reference
@INPROCEEDINGS{28_MIKULASEK2016_PIERS,
author = {MIKULASEK, Tomas and BLUMENSTEIN, Jiri and PROKES, Ales},
title = {Antennas utilized for intra-vehicle 3–11 GHz and 55– 65 GHz channel
measurement},
booktitle = {Progress in Electromagnetics Research Symposium, (PIERS)},
year = {2016},
pages = {4258–4262},
address = {Shanhai, China},
isbn = {978-1-5090-6093-1}
}

Abstract
The characteristics of the transmission channel inside the car are very important for future intra-car communication technologies. These technologies will create the small wireless networks for the distribution of data services such as internet, video, audio, etc. transmission. For these services, it is preferable to use the UWB frequency band from 3GHz to 11GHz because of the hardware support availability. An estimation of transmission channel characteristic is time-consuming and computationally demanding process. Presented paper deals with the channel transfer function estimation for different receiving antenna locations determined by the two dimensional grid. Proposed artificial neural network used for the analysis of the transmission channel is based on the feed forward and radial basis function structure. Neural networks have been optimized using measured channel transfer function to achieve better effectiveness, speed and accuracy.
bibTeX Reference
@INPROCEEDINGS{29_KOTOL2016_PIERS,
author = {KOTOL, Martin and PROKES, Ales and MIKULASEK, Tomas and RAIDA, Zbynek},
title = {Estimation the transmission between antennas using artificial neural
networks in the UWB band},
booktitle = {Progress in Electromagnetic Research Symposium (PIERS)},
year = {2016},
pages = {1465–1469},
address = {Shanghai, China},
isbn = {978-1-5090-6093-1}
}

Abstract
This paper deals with evaluating the effect of vehicle vibrations on the mm-wave intra-vehicular channel. As some of the vehicles’ vibration amplitude may reach the order of millimeters, i.e., the amplitude is comparable with the mm-wave wavelength (~5 mm), it can produce severe Doppler spreads. This paper evaluates Doppler spreads utilizing a mm-wave time-domain correlative channel sounder built into a vehicle which has been driven at different speeds on a variety of roads with a broad spectrum of surface quality.
bibTeX Reference
@INPROCEEDINGS{30_BLUMENSTEIN2016_PIMRC,
author = {BLUMENSTEIN, Jiri and VYCHODIL, Josef and POSPISIL, Martin and MIKULASEK,
Tomas and PROKES, Ales},
title = {Effects of Vehicle Vibrations on mm-Wave Channel: Doppler Spread
and Correlative Channel Sounding},
booktitle = {IEEE 27th Annual International Symposium on Personal, Indoor, and
Mobile Radio Communications (PIMRC)},
year = {2016},
pages = {398–402},
address = {Valencia, Spain},
isbn = {978-1-5090-3253- 2}
}

Abstract
The paper deals with a time varying intra-vehicle channel measurement in the 60 GHz millimeter wave (MMW) band using a unique time-domain channel sounder built from off-the-shelf components and standard measurement devices. The aim of the presented work is to describe the sounder architecture, the primary data processing technique, and preliminary results of measurements aimed at the effect of vehicle vibrations and twisting, and passengers moving in a car cabin. As the amplitude of the car cabin vibration and twisting had been supposed to be comparable with the MMW wavelength, some effect on the channel impulse response (CIR) and consequently on the delay-Doppler spread (DDS) was expected. Preliminary results confirm the correctness of this assumption and allow us to assess the effect of different above-mentioned phenomena. We tested the effect of driving the car on different types of road (bumpy road, flat road, highway, etc.). For comparison purposes we use DDS and statistics of CIR amplitudes calculated using the correlative technique applied to the pseudorandom binary sequence.
bibTeX Reference
@INPROCEEDINGS{31_PROKES2016_ATC,
author = {PROKES, Ales and VYCHODIL, Josef and POSPISIL, Martin and BLUMENSTEIN,
Jiri and MIKULASEK, Tomas and CHANDRA, Aniruddha},
title = {Time-Domain Nonstationary Intra- Car Channel Measurement in 60 GHz
Band},
booktitle = {Proc. of International Conference on Advanced Technologies for Communications
(ATC 2016)},
year = {2016},
pages = {1–6},
address = {Hanoi, Vietnam},
isbn = {1-4244-0800- 8}
}

Abstract
First results for frequency-domain channel measurements in a bus in the 60 GHz millimeter wave band are reported. The simple setup used consists of analog signal generator and scalar signal analyzer, instead of vector network analyzers which are costly and suffer from cable length limitation. Path loss values are computed directly from the frequency-domain data and log-distance model parameters are extracted. Next, assuming minimum phase channel, delay profiles are constructed from amplitude-only data following a Hilbert transform. Using the path loss and delay parameter values, the effect of seat position, passenger occupancy, reflections from glass window etc. are discussed in detail.
bibTeX Reference
@INPROCEEDINGS{32_CHANDRA2016_NTMS,
author = {CHANDRA, Aniruddha and MIKULASEK, Tomas and BLUMENSTEIN, Jiri and
PROKES, Ales},
title = {60 GHz mmW Channel Measurements inside a Bus},
booktitle = {Proceedings of the 8th IFIP International Conference on New Technologies,
Mobility and Security (NTMS)},
year = {2016},
pages = {1–5},
isbn = {9781479987856}
}

bibTeX Reference
@CONFERENCE{33_CHANDRA2016_BMW_SUMMER,
author = {CHANDRA, Aniruddha and PROKES, Ales},
title = {Intra-vehicle UWB channel modeling in frequency-domain},
booktitle = {BMW Summer School},
year = {2016},
address = {Germany},
note = {Poster}
}

Abstract
The dissertation is focused on channel measurements and modeling for vehicle-to-X communication and on localization. In order to realize an integrated intelligent transportation system (ITS), it is important to estimate channel features for intra-vehicle and out-of-vehicle scenarios. For this propose the following activities are carried out: simulation of the 802.11p PHY; comparison with 802.11a; channel measurements for different scenarios based on the 802.11p and ultra-wideband (UWB); creating channel models for 802.11p and UWB; UWB measurements to assess performance of localization.
– The vehicle-to-X communication is supposed on the IEEE 802.11p standard. The dissertation presents the differences between IEEE 802.11a and IEEE 802.11p physical layer standards through the simulation results of the transmission over a HIPERPLAN/2 channel. Further, the simulation of the 802.11p signal transmission over ITU-R M.1225 channel, which includes pedestrian and vehicle models with different relative delays and average power, is presented. The influence of the channel on the signal is analyzed using MATLAB simulation in terms of bit error rate (BER).
– The dissertation reports vehicular channel measurements in the frequency band of 5.8 GHz for IEEE 802.11p standard and for UWB (3-11 GHz). Experiments for both intra-vehicle and out-of-vehicle environments are carried out. It was observed that the large-scale variations (LSVs) of the power delay profiles (PDPs) can be best approximated through a two-term exponential decay model for the 802.11p protocol, in contrast to the Saleh-Valenzuela (S-V) model which is suitable for UWB systems.
– For each measurement, the LSV trend was used to construct the respective channel impulse response (CIR). Next, the CIR is used in 802.11p simulation to evaluate the BER performance, following a Rician model. The results of the BER simulation shows the suitability of the protocol for in-car as well as out-of-car wireless applications. The simulation for out-of-car parameters indicate that the error performances do not vary much and it is possible to determine an average BER curve for the whole set of data.
– The randomness in UWB channel for small positional variations around a car, parked in an underground garage, is reported. The path loss (PL) is found to be monotonically increasing with distance but varies randomly with angle and height and thereby renders signal strength based ranging inaccurate for such scenarios. On the other hand, arrival time of the first ray can be used for reliable estimation of distance, independent on transmitter angle or height. The number of clusters in the PDP is reduced with distance but the nature of the profile remains fairly consistent with angle. The S-V model parameters also vary with distance and height but their average values are close to the IEEE 802.15.3 recommended channel model.
– For localization applications the distance between the antennas is calculated exploiting the linear dependence of distance on delay from PDP. The coordinates of a transmitting antenna are found with the help of two receiving antennas following a two-dimensional (2-D) time-of-arrival (TOA) based localization technique. A comparison of the calculated coordinates with the original ones exhibits an error of less than 6% which supports the suitability of the proposed approach for localization of the cars.
bibTeX Reference
@PHDTHESIS{34_KUKOLEV2016_PHD,
author = {KUKOLEV, Pavel},
title = {Inter-Vehicle Communication Modeling and Around-Vehicle Localization},
school = {Brno University of Technology},
year = {2016},
type = {Doctoral Thesis}
}

Abstract
Komunikace a lokalizace uvnitř dopravních prostředků patří k velmi perspektivním oborům automobilové techniky. Vytvoření lokální bezdrátové sítě uvnitř vozidla může například zprostředkovat sdílení multimediálních souborů všem cestujícím nebo přenášet data mezi čidly, silovými akčními členy a řídícími jednotkami. Tato takzvaná „senzorová bezdrátová síť“ by mohla v budoucnu snížit nároky na použití měděných vodičů použitých v kabeláži automobilu, což by vedlo ke snížení ceny a hmotnosti vozidla a následně také k úspoře paliva. Lokalizace objektů uvnitř nebo v blízkém okolí vozidla pak může optimalizovat vyzařovací diagramy anténních systémů s cílem snížit elektromagnetické emise nebo zabránit neoprávněnému nastartování motoru. Aby mohly všechny výše uvedené komunikační a lokalizační systémy spolehlivě fungovat, je nutné znát dokonale prostředí, ve kterém se elektromagnetické vlny šíří, vytvořit jeho model a ten pak použít pro komplexní návrh systému. Vytvoření modelu však komplikuje skutečnost, že šíření elektromagnetických vln je ovlivněno řadou nežádoucích časově proměnných jevů, jako je mnohacestné šíření, rozptyl nebo stínění. Popisovaný výzkum je zaměřen na měření a modelování kanálů uvnitř dopravních prostředků v kmitočtových pásmech milimetrových vln (56–64 GHz) a UWB (3,1–10,6 GHz). V rámci výzkumných aktivit jsou demonstrovány metody měření jak v kmitočtové tak i v časové oblasti a popsány metody odhadu přenosové funkce, impulsní odezvy kanálu nebo výkonového profilu zpoždění dílčích složek, které jsou základem pro vytvoření statistického modelu kanálu. Důležitým výsledkem výzkumu je návrh a realizace unikátního měřicího systému, který umožňuje sledovat a vyhodnotit velmi rychlé změny vlastností přenosového prostředí a zkoumat tak například vliv pohybu cestujících nebo vliv vibrací a kroucení karoserie způsobených běžícím motorem nebo jízdou vozidla po vozovkách různé kvality.
bibTeX Reference
@INPROCEEDINGS{35_PROKES2016_RADIOKOMUNIKACE,
author = {PROKES, Ales and BLUMENSTEIN, Jiri and MIKULASEK, Tomas},
title = {M\v{e}\v{r}en\'{i} \v{s}\'{i}\v{r}en\'{i} elektromagnetick\'{y}ch
vln v automobilech pro \'{u}\v{c}ely komunikace a lokalizace},
booktitle = {Sborn\'{i}k p\v{r}edn\'{a}\v{s}ek konference Radiokomunikace},
year = {2016},
pages = {189–195},
address = {Pardubice, Czech Republic},
publisher = {UNIT s.r.o.},
note = {in Czech},
isbn = {1-4244-0000-1}
}

Abstract
In the paper, the localization of a person in a car by an artificial neural network is discussed. The position of a person is estimated from the channel transfer function between antennas affected by passengers. For the localization, two types the neural architectures are used – the feed-forward (FF) one and the radial basis function (RBF) one. The channel transfer function was measured at UWB frequencies (3 to 11 GHz) for all configurations of passengers. Each configuration was measured five times to consider the movement. Training and verification patterns were composed from measured values. Localization results are discussed in terms of estimation accuracy.
bibTeX Reference
@ARTICLE{36_KOTOL2016_RADIOENG,
author = {KOTOL, Martin and PROKES, Ales and MIKULASEK, Tomas and RAIDA, Zbynek},
title = {In-car Localization at UWB Frequencies by Neural Networks},
journal = {Radioengineering},
year = {2016},
pages = {1–5},
note = {Submitted}
}

Abstract
This paper describes a time domain channel sounder based on binary sequences. The channel sounder system consists of several off-the-shelf laboratory instruments connected together and controlled from PC. Frequency band of interest is the unlicensed millimeter wave band (MMW), 57–64 GHz. The system’s architecture, its parameters and two types (the Maximum Length Sequences and Golay complementary sequences) of excitation signals are presented and discussed. Main part of this paper is dedicated to description and analysis of the behavior of the system when non-linear components are used. Crucial feature of the proposed system is fast measurement speed enabling measurements of real scenarios with moving objects.
bibTeX Reference
@ARTICLE{37_VYCHODIL2016_EURASIP,
author = {VYCHODIL, Josef and POSPISIL, Martin and PROKES, Ales},
title = {60 GHz Time Domain Channel Sounder},
journal = {EURASIP Journal on Wireless Communications and Networking},
year = {2016},
pages = {1–17},
note = {Submitted},
issn = {1687-1499}
}

Abstract
In this paper, we study the capacity and symbol error probability (SEP) of generalized spatial modulation (GSM) multiple-input multiple-output (MIMO) systems using measured channel data that are obtained by channel sounding in an indoor office environment at 60GHz. Spatial modulation (SM) and GSM are emerging low-complexity MIMO schemes that have been extensively researched for low-GHz (below 6GHz) communications. Recently, they have been considered and shown to be promising also for millimeter – wave (mmWave) communications. In the simplest possible case, they require only one RF chain both at the transmitter (TX) and receiver (RX), and this makes the schemes especially attractive for mmWave communications, in which the number of RF chains needs to be as low as possible. Despite of a few early works on theoretical analysis of SM/GSM for mmWave communications, there have been no investigations using real-world channel data. We focus on the office line – of – sight (LOS) scenario and investigate three problems: 1) the performance of GSM using only the measured LOS component as compared to ideal pure LOS channels; 2) the impact of the (measured) non-LOS (NLOS) components on the channel capacity and SEP of GSM; and 3) possible simple modulation and reception algorithms for GSM that rely only on the LOS component of the channel. Our results on one hand validate the main claims of previous studies based on ideal pure LOS channels, but, on the other hand, also lead to novel findings that result from the consideration of NLOS components of the channel. Based on study using a practical (simple) receiver, one major conclusion is that NLOS components are harmful to the SEP of GSM and should be avoided.
bibTeX Reference
@ARTICLE{38_LIU2016_IEEE_TWC,
author = {LIU, Peng and BLUMENSTEIN, Jiri and PEROVIC, Nemanja Stefan and DI
RENZO, Marco and SPRINGER, Andreas},
title = {Experimental Assessment of Generalized Spatial Modulation MIMO over
60 GHz Indoor Channels},
journal = {IEEE Transactions on Wireless Communications},
year = {2016},
pages = {1–27},
note = {Submitted}
}

Abstract
This paper reports on a real-world wireless channel measurement campaign for in-vehicle scenarios in the Ultra Wide Bandwidth (UWB) frequency range 3-11 GHz. The effects of antenna placement in the vehicle’s passenger compartment, as well as the effects due to the presence of passengers are studied. The measurements have been carried out in the frequency domain and the corresponding channel impulse responses (CIRs) have been estimated by inverse Fourier transform. The in uence of a specific band group selection within the whole UWB range is also given. Statistical analysis of the measured channel transfer functions then gives a description of the wireless channel statistics in the form of a generalized extreme value process. The corresponding parameter sets are estimated and documented for all permutations of antenna placement and occupancy inside the vehicle’s passenger compartment. Further, we have carried out a feasibility study of an in-vehicle UWB based localization system based on time of arrival (TOA). The positioning performance is evaluated in terms of average error and standard deviation.
bibTeX Reference
@ARTICLE{07_BLUMENSTEIN2015_EURASIP,
author = {BLUMENSTEIN, Jiri and PROKES, Ales and MIKULASEK, Tomas and MARSALEK,
Roman and ZEMEN, Thomas and MECKLENBRAUKER, Christoph},
title = {Measurements of Ultra Wide Band In-vehicle channel – statistical
description and TOA positioning feasibility study},
journal = {EURASIP Journal on Wireless Communications and Networking},
year = {2015},
volume = {2015},
pages = {1–10},
number = {1},
issn = {1687-1499}
}

Abstract
A comparison of two variants of CLEAN, a time-domain serial subtractive deconvolution algorithm, is presented. Appropriate statistical metrics for assessing the relative merit of the deconvolution technique are identified in the context of intra vehicle ultra wide band transmission, and the better variant was selected based on its performance over a standard IEEE channel simulation testbed. The chosen method is then applied to extract important channel characteristics for a real-world channel sounding experiment performed inside a passenger car.
bibTeX Reference
@INPROCEEDINGS{08_CHANDRA2015_PECCS,
author = {CHANDRA, Aniruddha and BLUMENSTEIN, Jiri and MIKULASEK, Tomas and
VYCHODIL, Josef and POSPISIL, Martin and MARSALEK, Roman and PROKES,
Ales and ZEMEN, Thomas and MECKLENBRAUKER, Christoph},
title = {CLEAN algorithms for intra-vehicular time-domain UWB channel sounding},
booktitle = {Proceedings of the International Conference on Pervasive and Embedded
Computing and Communication Systems (PECCS)},
year = {2015},
pages = {224–229},
address = {Angers (France)},
isbn = {978-989-758-084-0}
}

Abstract
The article reports vehicular channel measurements in the frequency band 5.8 GHz for IEEE 802.11p standard. Experiments for both intra-vehicle and out-of-vehicle environments were carried out. It was observed that the large scale variations (LSVs) of the power delay pro—les (PDPs) can be best described through a two-term exponential decay model, in contrast to the linear models which are suitable for popular ultra wide band (UWB) systems operating in the 3-11 GHz band. The small scale variations (SSVs) are separated from PDP by subtracting the LSV, and characterized utilizing logistic, generalized extreme value (GEV), and normal distributions. Two sample Kolmogorov-Smirnov (K-S) tests validated that the logistic distribution is optimal for in-car, whereas GEV serves better for out-of-car measurements. For each measurement, the LSV trend was used to construct the respective channel impulse response (CIR), i.e. tap gains at di®erent delays. Next, the CIR information is fed to a 802.11p simulation tested to evaluate the bit error rate (BER) performance, following a Rician model. The BER results strongly vouch for the suitability of the protocol for in-car as well as out-of-car wireless applications.
bibTeX Reference
@ARTICLE{09_KUKOLEV2015_EURASIP,
author = {KUKOLEV, Pavel and CHANDRA, Aniruddha and MIKULASEK, Tomas and PROKES,
Ales and ZEMEN, Thomas and MECKLENBRAUKER, Christoph},
title = {In-vehicle channel sounding in the 5.8 – GHz band},
journal = {EURASIP Journal on Wireless Communications and Networking},
year = {2015},
volume = {2015},
pages = {1–9},
number = {1},
issn = {1687-1499}
}

Abstract
This contribution reports on in-vehicle radio propagation channel measurements for in-vehicle sensors in the Ultra Wide Bandwidth (UWB) frequency range 3-11 GHz and Millimeter Waves (MMW) 55-65 GHz. The effects of antenna placement in the vehicle’s compartment, line of sight (LOS) and non-line of sight (NLOS) scenarios, as well as the effects due to the presence of passengers are studied. Statistics of the measured transfer functions result in a description of the channel’s propagation loss and reverberation characteristics. We compare the UWB and MMW channel characteristics in detail.
bibTeX Reference
@INPROCEEDINGS{10_MECKLENBRAUKER2015_IMS,
author = {MECKLENBRAUKER, Christoph and PROKES, Ales and BLUMENSTEIN, Jiri
and ZEMEN, Thomas},
title = {Characterization of short range intra-vehicle wireless links comparing
ultrawideband 3–11 GHz and millimeter waves 55–65 GHz},
booktitle = {Proceedings of the IEEE MTT-S International Microwave Symposium (IMS),
Workshop on Advances of Microwave Technologies for Vehicular Communication},
year = {2015},
pages = {1–24},
address = {Phoenix (USA)},
note = {(Invited)}
}

Abstract
In this work, substrate integrated waveguide (SIW) slot antennas are proposed for 60-GHz channel characterization. The antennas consist of a group of three longitudinal slots placed in one or both broad walls of an SIW. Depending on the placement of the slot group, the SIW slot antenna achieves a directional or omnidirectional radiation pattern. An SIW slot antenna is naturally a narrow-band structure; however, using different self-resonant frequencies of the slots in the group ensures a wide operation frequency band (55–65 GHz). In this way, new utilization possibilities of the SIW slot antennas are proposed. The antenna design is performed in the full-wave electromagnetic solver ANSYS HFSS and verified by measurement. Experimental results validate good impedance matching and a directional or omnidirectional radiation pattern of the fabricatedantennas.
bibTeX Reference
@ARTICLE{11_MIKULASEK2015_MOTL,
author = {MIKULASEK, Tomas and LACIK, Jaroslav and RAIDA, Zbynek},
title = {SIW slot antennas utilized for 60-GHz channel characterization},
journal = {Microwave and Optical Technology Letters},
year = {2015},
volume = {57},
pages = {1365–1370},
number = {6},
issn = {1098-2760}
}

Abstract
Intra vehicular communication is an emerging field of research due to its potential applications in safety of passengers, navigational and localization aids for driver, and multimedia infotainment. This chapter describes the wireless channel sounding activities performed inside a typical passenger car under the SoMoPro and the GACR projects. Three different channel sounding architectures are developed for the purpose, namely direct pulse based sounding, frequency domain sounding and pseudo noise sequence based time domain sounding. Experiments with different placements of transmitter and receiver antennas inside the car were performed for both the ultra-wide-band and millimeter wave band. Channel transfer functions and impulse responses extracted from all these measurement campaigns are utilized to construct several deterministic and statistical channel models. The models are useful for designing intra vehicular wireless links and for devising novel vehicular localization algorithms.
bibTeX Reference
@INBOOK{12_CHANDRA2015_SCITEPRESS,
chapter = {Intra vehicular wireless channel measurements},
pages = {3–28},
title = {European Project Space on Information and Communication Systems},
publisher = {SCITEPRESS – Science and Technology Publications},
year = {2015},
author = {CHANDRA, Aniruddha and PROKES, Ales and BLUMENSTEIN, Jiri and KUKOLEV,
Pavel and VYCHODIL, Josef and MIKULASEK, Tomas and ZEMEN, Thomas
and MECKLENBRAUKER, Christoph},
address = {Portugal},
isbn = {978-989-758-155-7}
}