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Wireless vehicular communications and sensing technologies are key to enabling more advanced intelligent transportation systems (ITSs) with improved safety and efficiency. Within the realm of wireless communication, millimeter-wave (mmwave) technology has recently received much attention, providing rich spectrum resources to support the timely transmission of large amounts of data. This is especially important for vehicular applications because the number of sensors on modern vehicles is rapidly increasing and thus generating large amounts of data. To fully exploit this potential, understanding mm-wave vehicle-to-vehicle (V2V) propagation channels is crucial. In this article, we review the state of the art in mm-wave V2V channel measurements and modeling, describe recent directional V2V channel measurements performed in the 60-GHz band, and discuss future challenges to be addressed in mm-wave V2V channel measurements and modeling.

The lower THz bands are foreseen as candidates to achieve the data-rates demanded in the sixth generation (6G) of wireless communications. Hence, multiple measurements for characterization of propagation at these frequencies in different scenarios are being conducted all around the world. This also impulses activities on standardization of measurement equipment and methodologies to define common practices and make measurements from different actors comparable. Therefore, in the present paper we investigate the accuracy of a dual-polarized ultra-wideband channel sounder in the time, angular, and polarization domains by means of a verification methodology based on interferometry.

The second-order statistics of indoor directional channels are investigated using millimeter-wave (mmWave) band (30.4–37.1 GHz) ultrawideband (UWB) channel measurements. Considering two main mmWave system assumptions (high bandwidth and high beamforming gain), this paper aims to investigate the validity of the Rayleigh–Rice fading models for the cluster fading envelope. The results from the mmWave band study are compared to an already well-studied lower frequency FCC band (3.4–10.1 GHz). During the measurements, only selective objects (emulated multipath clusters in the propagation channel) are illuminated in a small lecture room. The experiments show that for both UWB channels, the complex received (Rx) signal is a circularly symmetric non-Gaussian random variable with highly correlated inphase (I) and quadrature (Q) components. These properties demonstrate that the intracluster multipath components (MPCs) structure is sparse. Consequently, modeling the cluster fading envelope with Rayleigh–Rice distribution is not realistic. Therefore, the sum-of-cisoids principle is used for intracluster multipath modeling which inherently considers a correlation between I and Q components. It has been established that a reasonably good approximation of the cluster fading envelope can be obtained with $N=3-6$ equal amplitude cisoids. However, we remark that Rayleigh–Rice models may become realistic cluster fading envelopes for narrowband mmWave systems.

Hybrid, mixed analogue/digital beam-forming architectures are a central research topic for the development of mm-wave communication for fifth generation. Most approaches are based on phase shifters in the analogue part, which are inherently narrowband. In this study, the authors evaluate the effects and performance of narrowband beam-steering on wideband signals using two different modelling approaches: spatial-narrowband model, in which the inter-antenna element delays are neglected, and spatial-wideband model, in which the inter-antenna element delays are considered. They show that neglecting the spatial-wideband effects on channel models overestimates the focusing of beam-forming, the expected delay spread reduction, and achievable data-rate with an increasing number of antennas and bandwidth. These effects are quantised by simulations using a realistic ray-tracing scenario at 60 GHz.

In this paper, impact of antenna directivity and bandwidth on the small scale fading statistics have been analyzed for millimeter-wave (mmWave) radio channels. For this purpose, small-scale fading measurements at the mmWave frequency band (58-62 GHz) are carried out using transmit and receive antennas with different antenna directivities (emulated beamforming gains). Measurements emulate a non line-of-sight scenario when the communication between transmit and receive antennas is possible only through a single multipath cluster. In order to compare results, measurements in a line-of-sight scenario with omni-directional antennas are also carried out for reference purpose. Considering two main mmWave system features i.e., high antenna directivity and higher system bandwidth, we report the following results: 1) Randomness/fading in the received signal magnitude vanishes with an increase in bandwidth. 2) The channel impulse response h (t, τ) does not remain a wide-sense stationary (WSS) random process in the slow-time domain i.e., along t, where, the fast-time domain refers to the dimension along τ. 3) Measured channels are WSS in the frequency domain and the coherence bandwidth increases when propagation channels are illuminated with high gain antennas.

Vehicle-to-vehicle (V2V) channels exhibit unique properties due to the highly dynamic environment and low elevation of the antennas at both ends of the link. Of particular importance for the behavior of V2V channels, and consequent reliability of the communication link, is the severity and dynamics of blockage of both the line-of-sight and other multipath components (MPCs). The characteristics of blockage become more important as the carrier frequency increases, and the ability of the signal to penetrate through objects diminishes. To characterize the effects of vehicle blockage, we performed V2V channel measurements in four different frequency bands (6.75, 30, 60, and 73 GHz) in urban and highway scenarios. We analyzed the impact of the blocker size and position on the received power and fast fading parameters, as well as the frequency dependence of these parameters under blockage. Our results show that there is a strong influence of the size of the blocking vehicle on the blockage loss and the angular/delay spread. The position of the blocker relative to the transmitter and receiver also plays an important role. On the other hand, the frequency dependence is quite limited, with the blockage loss increasing slightly and the number of scattered MPCs reducing slightly as frequency increases. The main conclusion of this paper is that V2V communication will be possible in high (millimeter-wave) frequencies, even in the case of blockage by other vehicles.

The characterization of propagation at mm-waves and THz is obtaining relevance since they are expected to be the frequency bands of the future wireless generations. Hence, measurements conducted all around the world with different equipments need to be comparable by establishing common methodologies and best-practice guidelines. As an example, all measurements are affected by noise, but its estimation and removal are not standardized. Therefore, in the present paper we define a methodology on the estimation of the noise floor and the cut-off margin for its subsequent removal. We firstly analyse the influence of the channel sounder noise floor on the estimation of different propagation parameters directly from the measured channel impulse responses (CIRs), showing the need of its removal before any processing of the measurements. Later, we introduce an algorithm to estimate the noise floor in the presence of signal, and the cut-off margin. Finally, we evaluate its performance empirically with measurements.

Positioning and localization is one of the key features in the 5G and beyond wireless networks. Since accuracy strongly depends on the channel conditions, channel models are of special importance for the testing and development of such applications. While several localization methods are based on the time of arrival (ToA) and time-difference of arrival (TDoA), stochastic spatial channel models (SCMs) as the 3GPP don’t consider absolute values on the delays of the non-line of sight (NLOS) multi-path components (MPCs), making these models not appropriate for these applications. Therefore, we investigate the time and angular characteristics of the first multi-path component (FMPC) using multi-band ray tracing (RT) simulations in order to extend stochastic SCMs to support localization applications in NLOS.

This contribution proposes modeling methods for MIMO-TDL channel models under new evaluation method, which is non-WSSUS. V2X channels cannot be assumed to follow the WSSUS assumption due to high inherent mobility. It can be extended to non-WSSUS by employing an ON/OFF process (persistence process). An algorithm to select taps and estimate their parameters from measured data is illustrated. Meanwhile, the slow and fast fading is separated from received signal to assess the fading distribution of taps. The analysis investigates correlation coefficient among taps persistence process, as well as, among taps amplitude. Additionally, an approach is discussed to develop a time varying MIMO-TDL model, whose parameters are varying over time.

In the present paper we introduce unique double-directional dual-polarized measurements at 190 GHz in a conference room with the aim of characterizing propagation for channel modelling and beam-forming applications. Assisted by ray-tracing, multiple scatterers have been identified, showing a rich multi-path environment. Investigations have shown that polarization diversity increases spatial diversity and a more deterministic modelling approach in polarization is needed to avoid overestimating polarization diversity gains.

Industry 4.0 is the scenario in which the 5G and beyond networks are expected to show all their potential. However, while propagation at sub-6 GHz has been widely investigated in industry environments, mm-waves propagation and channel modelling in those scenarios is still under early research. Therefore, we introduce novel simultaneous multiband ultra-wideband measurements at 6.75 GHz and 30 GHz in LOS and NLOS with RX below and above clutter level. This unique set-up allows a direct comparison between the sub-6 GHz and mm-wave channel. Results have shown larger specular to dense multi-path components power ratio and shorter large-scale parameters at mm-waves.

Development of a comprehensive channel propagation model for high-fidelity design and deployment of wireless communication networks necessitates an exhaustive measurement campaign in a variety of operating environments and with different configuration settings. As the campaign is time-consuming and expensive, the effort is typically shared by multiple organizations, inevitably with their own channel-sounder architectures and processing methods. Without proper benchmarking, it cannot be discerned whether observed differences in the measurements are actually due to the varying environments or to discrepancies between the channel sounders themselves. The simplest approach for benchmarking is to transport participant channel sounders to a common environment, collect data, and compare results. Because this is rarely feasible, this paper proposes an alternative methodology – which is both practical and reliable – based on a mathematical system model to represent the channel sounder. The model parameters correspond to the hardware features specific to each system, characterized through precision, in situ calibration to ensure accurate representation; to ensure fair comparison, the model is applied to a ground-truth channel response that is identical for all systems. Five worldwide organizations participated in the cross-validation of their systems through the proposed methodology. Channel sounder descriptions, calibration procedures, and processing methods are provided for each organization as well as results and comparisons for 20 ground-truth channel responses.

This contribution presents propagation measurements at 60 GHz in indoor non-line of sight scenarios. Besides analysing the measurements, the authors have considered several system aspects, such as bandwidth and directivity in order to investigate the small-scale behaviour of the radio channel after beam-forming. The results show that due to the high resolution in the angular and time domain achievable by large antenna arrays and wideband signals, the fading is significantly reduced and the equivalent transmission channel becomes more sparse and deterministic. These insights represent an essential source of information for future systems design and the ongoing channel modelling activities for systems operating at mm-waves.

This paper presents 70–77 GHz wideband channel characteristics of delay, spatial, and polarimetric domains for small office and entrance hall scenarios. Based on measured multidimensional power spectra of delay, and directions (i.e., azimuth and elevation) of departure and of arrival, multipath clusters were detected using the K-means, threshold-based, and Gaussian-mixture-model clustering algorithms. The spatial positions and directions of clusters, including the first- and last-hop scatterers, are determined using a measurement-based ray tracer method. Our experimental analysis reveals that the composite and cluster-level channel behaviors are considerably dependent on the geometry of environments, the interaction/bouncing order between a wave and objects, the position of transmitter and receiver, the underlying antenna type, and the polarimetric combination. The angular spread of arrival is observed larger than that of departure, and the characteristics for the horizontal polarization are comparable with those for vertical polarization. Our results also manifest the merits of threshold-based clustering algorithm in terms of clusters’ compactness, separation, and exclusiveness. We further find that the identified interaction points exhibit excellent agreement with real physical objects existing in the environment. Based on these results, an indoor stochastic channel model is established not only for the composite parameters and cluster characteristics, but also for the first- and last-hop scatterers’ position, direction, and their dispersive statistics. This model can be used to generate channel realizations of reasonable spatial consistency.

The World Radiocommunication Conference 2015 (WRC-15) identified a number of frequency bands between 24 and 86 GHz as candidate frequencies for future cellular networks. In this article, an extensive review of propagation characteristics and challenges related to the use of millimeter wave (mm-wave) in future wireless systems is presented. Reference to existing path-loss models including atmospheric and material attenuation in recommendations of the International Telecommunication Union (ITU) in Geneva, Switzerland, is given, and the need for new multidimensional models and measurements is identified. A description of state-of-the-art mm-wave channel sounders for single and multiple antenna measurements is followed by a discussion of the most recent deterministic, semideterministic, and stochastic propagation and channel models. Finally, standardization issues are outlined with recommendations for future research.

We introduce simultaneous multi-band ultra wideband double-directional measurements at 6.75 GHz, 30 GHz, and 60 GHz in a corner scenario at a "T" intersection in an urban environment. We analyse the influence of the dynamics from LOS to NLOS on the large-scale parameters, showing that the propagation channel offers similar scattering opportunities at the sub-6 GHz and the mm-wave bands. In addition, we discuss the possibility of utilizing the directional information from sub-6 GHz to steer beams in the mm-waves bands.

In the present paper we introduce the results of simultaneous multi-band ultra-wideband measurements at 6.75, 30, and 60 GHz in a street canyon scenario under LOS in Germany. This is the first part of a street canyon measurements series using the same channel sounder in different parts of the world. The aim of these measurements is to analyse and compare the propagation characteristics with multi-band channel modelling in view. We show that from the propagation perspective, mm-waves offer very similar opportunities than the well known and exploited sub-6 GHz bands.

The small scale fading measurements at the 60 GHz frequency band are carried out to investigate the second-order statistics of a fading multipath cluster. The cluster is illuminated with different gain antennas (emulated beamforming gains). The analysis reveal that the measured channel impulse response (CIR) is approximately circular (or circularly symmetric) with correlated inphase (I) and quadrature (Q) components. These properties correspond to the sparse multipath channels and are different from the Rayleigh/Rician fading channels which assume that the I and Q components are mutually uncorrelated colored Gaussian variates. These differences prevent the application of the Rayleigh/Rice fading models in the intra-cluster multipath modeling.

We perform simultaneous vehicle-to-vehicle (V2V) multi-band double-directional measurements at 6.75 GHz, 30 GHz, and 60 GHz in a street canyon environment. We analyse both line-of-sight channels and those obstructed by vehicle blocker. For the different bands, we analyse delay spread, angular spread, vehicle blockage loss, and path loss. Finally, we discuss how the system aspects influence the radio channel.

Using Sum-Of-Cisoids (SOC) principle along with a deterministic parameter computation method, this paper provides studies on modeling of the intra-cluster number of scattered multi-path components (MPC) N and their amplitudes c n . Modeling objective is to ensure that the fading statistics of the receive (Rx) signal magnitude of the measured beam-formed channels for an emulated cluster; match precisely with the deterministic samples (channel snapshots) of the simulation model. It has been found that measured Rx signal magnitude can be excellently approximated with N = 2 — 6 subpaths/sinusoids which is much lower than 3GPP assumed number i.e. N = 20.

In the present paper we introduce novel simultaneous multi-band double-directional ultra-wideband measurements at 6.75 GHz, 30 GHz, and 60 GHz in an urban V2V scenario. The objective is to characterize propagation differences between the measured bands in view of correlated multi-band channel models. Furthermore, we investigate the impact of other vehicles blocking the V2V link by performing measurements with different blocker sizes (specifically, a passenger car and a large van). The shadowing effects and the correlation between intra-cluster delay spreads and large scale parameters are investigated in the different bands.

Our goal is to identify if limited channel-state information is sufficient to mitigate interferences between the stations of a wireless mobile backhaul network, which is especially of great importance if the network employs full-duplex operation or terrestrial and satellite links sharing the same spectrum. We analyze and compare the signal-to-interference-and-noise ratio of plain beam steering and zero-forcing beam steering for a millimeter-wave backhaul network with limited channel-state information where only the positions of the stations are known, while buildings and other possible sources of multipath components are unknown. Numerical analyses based on raytracing in a realistic urban scenario reveal that zero-forcing beam steering outperforms plain beam steering by about 12 dB. Furthermore, we compare the steering approaches to block diagonalization with full channel-state information as a reference. For situations with low signal-to-noise ratio as in wide-band communications, zero-forcing beam steering can achieve a similar signal-to-noise-and-interference ratio to block diagonalization. We conclude that knowing the positions of wireless backhaul stations obviates the need for expensive channel estimation.

In this paper, directional small scale fading measurements are used to extract the fading statistics of the received signal magnitude and the parameters of the underlying stochastic (Rayleigh/Rician) model. After that sum-of-cisoids (SOC) principle is used to model the deterministic samples (channel snapshots) of the stochastic model with a special focus on the number of sinusoids/scatterers and their weights. It has been established that theoretical and simulated results of the SOC fading channel simulator provide an excellent approximation of the measured received signal magnitude per cluster with a small number of sinusoids i.e. $N=4$.

Large absolute channel bandwidths at millimeter wave (mmWave) frequencies and more directional antenna gains may lead to quasi-deterministic (less random) channel fading behavior. Randomness in the cross polarization discrimination (XPD) is an attribute related to the channel fading behavior. In narrow-band channels, it is usually modeled as a log-normal random variable. From channel modeling perspectives, XPD power level in a particular propagation environment and its degree of randomness are of fundamental interest. In this paper, XPD behavior is characterized as a function of bandwidth in 4 different propagation setups including line of sight (LOS), reflections from black board, a rough wall and double bounce reflections from both surfaces. It has been observed that in all cases, the coefficient of variation of XPD around its mean value reduces exponentially with an increase in channel bandwidth demonstrating an evolution towards quasi-deterministic channel behavior. Additionally, a 5–10 dB difference in XPD values has also been observed between narrow-band and UWB channels in the considered propagation setups.

In the present paper we evaluate the performance of a hybrid digital/analog multi-beam beam-forming architecture with polarization and delay compensation using time reversal (TR). Double-directional, ultra wideband dual-polarized channel measurements at 70 GHz in a conference room have been used to emulate the channel. The use of multiple beams to mitigate human shadowing has been evaluated and the temporal and spatial focusing of time-reversal to reduce inter-user interference.

In the present paper we analyse small-scale fading of reflections at 60 GHz using different antennas and bandwidths. The aim is to investigate the deterministic property of the channel in view of modelling and deployment of systems with larger bandwidths and higher directivity. We have investigated the scattering effect of a reflection on a wall emulating a beam-former in a NLOS condition. The results show that the distribution of the amplitudes fit better with a Rician than a Rayleigh distribution. Furthermore, we show that an increasing bandwidth and directivity increases the k-factor, supporting the idea of deterministic paths apart from the LOS.

A wireless channel is always composed of both deterministic and stochastic multi-path components. A high Rician K-factor increases the contribution of deterministic channel components, thereby reducing the significance of stochastic parts of a channel. This paper focus at the investigative analysis of K-factor and fading depth to analyze the deterministic behavior of a channel under a certain bandwidth. In this paper, 4 different propagation setups have been studied including a LOS, reflections from black board and wall are considered due to their different surface roughness and double bounce reflections from both surfaces. It has been observed that in all propagation cases, small scale fading depth asymptotically converges towards zero dB whereby K-factor increases with bandwidth. Results also show that the de-polarization of a signal increases its amplitude fading. This effect is much more significant at lower bandwidths but an increase in bandwidth reduces the difference in fade depths between polarized and depolarized signals. These observations lead to a conclusion that channel tend to be more deterministic at higher bandwidths.

If a channel is frequency dependent then Uncorrelated Scattering (US) (a narrow-band assumption) don't hold. This has a significant impact at the considered channel modeling methodology as delay and angular dispersion of waves can no longer be studied independently because the small scale fading of individual multipath components become correlated. In this paper, we investigate the frequency dependence of the 30 GHz millimeter-Wave (mmWave) Ultra-Wide band (UWB) channel. Our indoor small lecture room measured channel results show that both delay and angular spreads vary significantly for different frequencies within a measured UWB channel. This is due to different interactions with objects in the environment due to significant difference in the comparative wavelengths. Therefore, we stress that mmWave-UWB channel modeling methodology must take into account the frequency dependence of channel parameters. In order to support its significance, we have also provided an evidence from mmWave system architecture point of view.

The use of large-size antenna arrays to implement pencil-beam forming techniques is becoming a key asset to cope with the very high throughput density requirements and high path-loss of future millimeter-wave (mm-wave) gigabit-wireless applications. Suboptimal beamforming (BF) strategies based on search over discrete set of beams (steering vectors) are proposed and implemented in present standards and applications. The potential of fully adaptive advanced BF strategies that will become possible in the future, thanks to the availability of accurate localization and powerful distributed computing, is evaluated in this paper through system simulation. After validation and calibration against mm-wave directional indoor channel measurements, a 3-D ray tracing model is used as a propagation-prediction engine to evaluate performance in a number of simple, reference cases. Ray tracing itself, however, is proposed and evaluated as a real-time prediction tool to assist future BF techniques.

In the present paper we introduce the architecture of a hybrid digital / analog beam-forming with polarization compensation. To evaluate the performance of this architecture we use double-directional, ultra wideband dual-polarized channel measurements at 70 GHz that have been carried out in a small-office environment scenario at the TU Ilmenau. Different positions of Tx and Rx have been measured using horn antennas. The channel impulse responses (CIR) have been processed to emulate a communication system with analog beam-forming capabilities. A single data stream adopting single beam and multi-beam beam-forming strategies has been tested with the measured data, showing an improvement in performance achieved by adopting such an architecture.

The vision of multi Gbit/s data rates in future mobile networks requires the change to millimeter wave (mm-Wave) frequencies for increasing bandwidth. As a consequence, new technologies have to be deployed to tackle the drawbacks of higher frequency bands, e.g. increased path loss. Development and verification of those novel technologies required an understanding of the propagation effects at mm-Wave which enabled by channel sounding measurements and analysis. Due to the variety of considered frequency bands and the necessity of spatial resolved measurements for e.g. testing of beamforming approaches, measurement duration and comparability becomes problematic. This paper presents multi-band channel sounder architectures, usable to measure up to four frequency bands simultaneously. Furthermore, we present a measurement campaign, featuring full polarimetric and directional resolved dual-band measurements, which comprises the microwave band at 10 GHz and the mm-Wave band at 30 GHz. Preliminary analysis results are presented.

Double-directional, ultra wideband dual-polarized channel measurements at 70 GHz have been carried out in a small-office environment. The aim of these measurements is to study the temporal, directional, and polarization properties of the channel for modelling purposes of the future wireless communication systems at mm-waves. A highly deterministic behaviour of the channel and the environment has been identified, as well as the limitations of only parameterizing channel models as WINNER for the new mm-wave channel models.

Owing to the limitation in bandwidth of currently used frequency bands, future fifth generation (5G) mobile networks will need to operate at higher frequencies. However, one important step in the research activities for the next generation of mobile networks is the broadband fully polarimetric analysis of the multipath propagation in dynamic single and multiuser scenarios under time-variant shadowing environments in millimetre- wave (mm-wave) channels. This paper presents a channel sounding campaign at 70 GHz in an urban outdoor scenario focusing on broadband channel characteristic at mmwave. For the measurements a novel dual-polarized (DP) ultrawideband (UWB) multi-channel sounder (DP-UMCS) architecture, developed at the TU Ilmenau for propagation measurements in cellular networks, was used to study the directional and polarization properties of the channel in view of the future wireless communication systems.

Increasing data rates in mobile networks require new technologies for the next generation of mobile communication systems such as massive MIMO, device-centric architectures, smarter devices, machine-2-machine communication etc. However, one important step to reach the goal of 100 GBit/s will be use of higher bandwidth. Owing to the limitation in bandwidth of currently used frequency bands, future fifth generation (5G) mobile networks will need to operate at higher frequencies. Analysis of the multipath propagation in dynamic single and multi-user scenarios under time-variant shadowing environments with high bandwidth requires a millimetre-wave (mm-wave) channel sounder (CS). It must provide ultra-wideband (UWB) real-time operation with multiple antennas and a high dynamic range. In addition, polarimetric information is needed to fully characterise the wireless channel, e.g. for cases of polarisation misalignment at the mobile device. This paper presents a novel UWB dual-polarised (DP) mm-wave channel sounder architecture for real time measurements in 5G mobile networks to overcome these requirements. We also show measurement data to motivate the need for polarimetric double-directional measurements.

Owing to the increasing data rates, future 5G mobile networks will need to operate at higher frequencies and bandwidths. To investigate new techniques for those networks, channel sounding is essential for measuring and analysing the multipath propagation in single and multi-user situations under time-variant shadowing environments. This requires a challenging design of the millimeter-wave (mm-wave) channel sounder (CS) - it must provide ultra-wideband (UWB) real-time operation with multiple antennas and a high dynamic range. In addition, polarimetric information is needed to fully characterise the wireless channel, e.g. for cases of polarisation misalignment at the mobile device. This paper presents a novel UWB dual-polarised mm-wave channel sounder architecture for real time measurements in 5G mobile networks and motivates the need for polarimetric measurements with experimental data collected at 60 GHz.

Directional, dual-link, quad-polarized 60 GHz channel measurements have been carried out in a small-office environment. Purpose of the measurements is to study the directional properties of the channel in view of future multi-gigabit system adopting beam-forming or macro-diversity solutions. The impact of polarization on the characteristics of the channel is also addressed in the study.

Frequency bands above 6 GHz are being considered for future 5G wireless systems because of the larger bandwidth availability and of the smaller wavelength, which can ease the implementation of high-throughput massive MIMO schemes. However, great challenges are around the corner at each implementation level, including the achievement of a thorough multi-dimensional characterization of the mm-wave radio channel, which represents the base for the realization of reliable and high-performance radio interfaces and system architectures. The main properties of the indoor radio channel at 70 GHz, including angular and temporal dispersion as well as an assessment of the major interaction mechanisms, are investigated in this study by means of UWB directional measurements and ray tracing simulations in a reference, small-indoor office environment.

According to the current prospect of allocating next generation wireless systems in the underutilized millimeter frequency bands, a thorough characterization of mm-wave propagation represents a pressing necessity. In this work, an “item level” characterization of radiowave propagation at 70 GHz is carried out. The scattering properties of several, different objects commonly present in indoor environment are investigated by means of measurements carried out in an anechoic chamber. The measured data have been also exploited to tune some parameters of a 3D ray tracing model.