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ABSTRACT: In the last years EHF (Extremely High Frequency / 30-300 GHz) band is acquiring more and more interest in different fields, such as telecommunications, radar applications and Earth observation, due to advantageous characteristics. Actually, the higher operating frequency with respect to traditional ranges (Ka and lower) allows the achievement of some advantages: no crowding in frequency and hence reduced interference, large bandwidth availability, reduced antenna and electronic components size, and more security in point-to-point links due to smaller beamwidth. Moreover, the increase of frequencies allows the realization of, with respect to lower bands, high resolution applications, as radar images and Earth Observation sensors. However, although W band is an attractive range, it is yet an experimental frontier since no telecommunication mission has been carried out and the technology development at this frequency is still poor, costly and relatively not ready. However, some specific applications, such as radar and radio-astronomy, and just for some frequencies (typically around 94-96 GHz), make an exception. Considering this context, a very significant and preliminary step to useful W band exploitation for terrestrial and satellite telecommunications is represented by the analysis and the validation of a terrestrial link operating at these frequencies with the capability of carrying out transmission/reception experiments. In this frame, the University of Rome, "Tor Vergata" in collaboration with the company Rheinmetall Italy is carrying out an experiment based on the establishment of a W band point-to-point terrestrial link over a distance of some kilometers between the University of Rome "Tor Vergata" (Rome) and Villa Mondragone (Frascati, near Rome). The work aims at showing an overview of the preliminary design of the experimental W band terrestrial air link. It will be very useful mainly for two reasons: firstly, in order to provide a test-bed for evaluating at-
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mospheric effects (fading and scintillation, along with amplitude, phase, and polarization distortion) that could compromise the performance of satellite-to-ground communications systems operating at these frequencies; and secondly to verify performance of W band critical technology. The last part of the work investigates the possibility of using, in addition to the traditional approach, Impulse Radio Ultra Wide-Band (IR-UWB) technology for realizing very high bit-rate point-to-point Line Of Sight (LOS) last mile links beyond 60 GHz. This paper will firstly provide a preliminary orographic and propagation analysis of the terrestrial link. Then, a detailed insight into link architecture and transmitter/receiver schemes will be reported taking into account constraints related to the characteristic of the available HardWare (H/W) in Rheinmetall Italy. Finally, an accurate link budget for dimensioning the system in terms of maximum link capability will be reported.
Aerospace Conference, 2011 IEEE; 04/2011
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ABSTRACT: To detect and measure all the positions and movements of human hands, a data glove with bend sensors presents relevant advantages with respect to other solutions based on video-cameras. However, most of these advantages would be lost if wired connectivity is utilized. This paper presents the implementation of a wireless connection based on ZigBee protocol specifications to transmit the acquired data block from the sensorized glove to a computer with the addiction of a graphical interface to display the hand movements in real-time. The design choices are discussed and the experimental procedure is described considering a new power saving mechanism. Moreover, a power saving mechanisms has been implemented and its effectiveness has been assessed via measurements.
Applied Sciences in Biomedical and Communication Technologies (ISABEL), 2010 3rd International Symposium on; 12/2010
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ABSTRACT: While cellular and WLAN (Wireless Local Area Networks) at low frequencies (1-5 GHz) constantly struggle with the quasi-saturation of spectrum, the EHF band (30-300 GHz) has huge swathes of band available at no cost. The recently allocated 71-76 GHz and 81-86 GHz bands provide an opportunity for Line Of Sight (LOS) links for directional point-to-point ”last mile” links. This work focuses on the design and BER (Bit Error Rate) performance evaluation of a W band IR-UWB architecture based on an 85 GHz up-conversion stage of train of ns Gaussian pulses in terms of phase noise, and Low Noise Amplifier (LNA) and High Power Amplifier (HPA) distortions. Simulation results show that BER performance, in presence of RF non-linearities, for an IR-UWB transceiver architecture operating at W band (with same data rate and bandwidth) are better than a 2-FSK scheme working in a similar scenario.
Ultra-Wideband (ICUWB), 2010 IEEE International Conference on; 10/2010
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ABSTRACT: In this paper an analysis on the use of Adaptive Coding and Modulation (ACM) techniques for EHF satellite communications is presented with reference to the DVB-S2 standard. The analysis is focused on W-band communication links and includes an optimization of DVB-S2 ACM thresholds of the received Signal to Noise Ratio (SNR) for Extremely High Frequency (EHF) links. The simulation model includes rain fading and amplifier nonlinearities which can not be neglected for the performance analysis and optimization of real systems in W-band.
Aerospace Conference, 2010 IEEE; 04/2010
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ABSTRACT: In this work authors investigate the use of IR (Impulse Radio) UWB (Ultra-Wide Band) technique for satellite communications at frequency bands beyond Q/V bands. In particular, the paper shows how an IR UWB communication system is sensitive to typical hardware non-idealities at those frequency bands and compares its performance with the ones of a more classical continuous wave communications system with FSK (Frequency Shift Keying) modulation. Simulation results show that BER (Bit Error Rate) performance for IR-UWB Payload (P/L) architecture operating in W band (with same data rate and bandwidth occupation) are better than a 2-FSK scheme operating at same frequencies range and considering Dirty RF (Radio Frequency) effects.
Aerospace Conference, 2010 IEEE; 04/2010
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ABSTRACT: Recent large scale disasters have highlighted the importance of a robust and efficient public safety communication network
able to coordinate emergency operations even when existing infrastructures are damaged. The Incident Area Network (IAN) is
a self-forming temporary network infrastructures brought to the scene of an incident to support personal and local communications
among different public safety end-users. In this work we are interested in investigating how the High Altitude Platform (HAP)
can effectively support Multimedia Broadcast/Multicast Service (MBMS) in a scenario wherein the preexistent terrestrial network
is not available. To this aim, we propose an efficient policy of Radio Resource Management (RRM) based on cooperation framework
between HAP and Mobile Ad-Hoc NETwork (MANET). The proposed solution has been successfully tested through a comprehensive
simulation campaign.
KeywordsIncident Area Networks-Cooperative Multicast-MBMS-HAP-MANET-WiFi
12/2009: pages 436-450;
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ABSTRACT: In the current scenario, where it is becoming very important for many Health Care Monitoring System to provide non-invasive and non-contact measurements, this paper presents a novel monitoring system for vital signs based on the Frequency Modulated-Ultra Wide Band (FM-UWB) technology. First of all, an analysis of the error introduced by each block of the transceiver device is performed in order to better understand the achievable resolution under no ideal working conditions. Then, a comparison with an IR-UWB monitoring system is performed in terms of sensitivity. As it is expected, the FM-UWB radar, which is a continuous wave radar, can achieve the same resolution also working much lower SNRs than IR-UWB systems. This means that proposed system can work also with lower power levels than an IR-UWB device. Moreover, our simulation confirms that the FM-UWB system can achieve the desired resolution (of the order of mm) for the context of interest (heart-beat, respiration rate monitoring).
Applied Sciences in Biomedical and Communication Technologies, 2009. ISABEL 2009. 2nd International Symposium on; 12/2009
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ABSTRACT: This letter addresses the application of Linear Dispersion Codes (LDC) in space and frequency domains in Single Carrier-Frequency Domain Equalization (SCFDE) systems. Space-frequency (SF)-LDCs are more suitable than space-time (ST) LDC in high mobility environments. However, the application of LDCs in space and frequency domains in SCFDE systems is not straightforward as in orthogonal frequency division multiplexing (OFDM) systems because in this case there is no direct access to subcarriers at the transmitter. This letter shows that it is possible to induce a target SF symbol dispersion in SCFDE by using a simple linear pre-coder and a conventional LDC that spreads the symbols in time and space domains according to specific ST dispersion matrices. The letter shows how to derive the ST dispersion matrices to be used at the transmitter as a function of the dispersion matrices describing the target SF dispersion. The presented procedure can be applied to both pure transmit diversity and pure multiplexing schemes, which are special cases of LDCs. Therefore, the proposed scheme provides a low complexity implementation of any dispersion in space and frequency over SCFDE systems, which alternatively would require the use of FFT/IFFT also at the transmitter side. The letter also shows a performance comparison of SF-LDCs and ST-LDCs in a typical propagation environment for future radio systems. The comparison confirms the suitability of using the dispersion in frequency rather than time for a wide range of coherence bandwidths.
IEEE Transactions on Wireless Communications 12/2009; · 2.59 Impact Factor
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ABSTRACT: In this paper, main single carrier (SC) and multicarrier (MC) systems with frequency domain equalization (FDE) are reviewed with the objective to identify key features of the evolution path of air interfaces towards 4G. In particular, this paper shows that the FFT/IFFT operation can be seen as the concatenation of two operations: S/P conversion and spreading. We show that the transmitter of an OFDMA system performs a S/P conversion and a multiplication with specific complex spreading codes. By replacing the orthogonal complex spreading codes of this equivalent OFDMA system, with traditional orthogonal spreading codes that are used in DS-CDMA systems, for instance Walsh-Hadamard codes, we achieve a novel multicode-CDMA system. The comparison of this novel SC transmission scheme with other SC and MC systems shows that the novel SC system has almost the same performance as OFDMA and also similar PAPR. On the other hand, it has a pretty different behavior wrt other SC systems such as IFDMA and DS-CDMA with FDE.
Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology, 2009. Wireless VITAE 2009. 1st International Conference on; 06/2009
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ABSTRACT: This paper presents a novel human joint motion recording method, The recorded data are sent to the receiver, which is placed in the close proximity or in the same room with the patient, via a wireless short-range communications system that guarantees 3 days of battery life. This method exploits commercially available bend sensors to convert mechanical human joint movements into electric signals which are then acquired, pre-processed, wireless transmitted and post-processed. We propose a novel way of sensor's application, underlying advantages and drawbacks which could be drastically reduced by electronic circuitry anyway. The network configuration and the specific air interface are chosen to satisfy system requirements in terms of data rates, battery autonomy, and mobility.
Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology, 2009. Wireless VITAE 2009. 1st International Conference on; 06/2009
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ABSTRACT: Past crises all over the world (09/11, tsunami, etc.) have highlighted the importance of the availability of critical up-to-date information in real-time at the place where required. The key need is, consequently, for reliable communication systems to coordinate emergency operations even when existing infrastructures are damaged. In this case, rapidly deploying ad-hoc networks in the disaster area is a feasible solution. Incident Area Network (IAN), are self-forming temporary network infrastructures brought to the scene of an incident to support personal and local communications among different public safety end-users. This paper aims at defining the system architecture of IANs where the cooperation among terminals is foreseen. Furthermore, several open issues are identified and possible solutions are proposed.
Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology, 2009. Wireless VITAE 2009. 1st International Conference on; 06/2009
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ABSTRACT: Wireless personal area networks (WPANs) are short-range ad-hoc networks centered around a person that make use of unlicensed bands for data transmission. Several transmission schemes such as ultra wide band (UWB) or spread spectrum (SS) have been proposed for both Low Data Rate (LDR) and High Data Rate (HDR) WPANs. Such transmission schemes are designed to comply with the different requirements of LDR and HDR WPANs. These requirements are complementary in terms of data rate, but not in terms of coverage. It is thus an interesting topic to integrate LDR and HDR air interfaces in a dual-mode wireless device. However, because of the unlicensed nature of WPANs, interference issues exist between devices associated with different WPANs. These issues easily arise when a LDR air interface is closely located with a HDR air interface. This paper investigates the effects in terms of performance degradation related to the interference generated by closely-located HDR and LDR WPAN devices.
Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology, 2009. Wireless VITAE 2009. 1st International Conference on; 06/2009
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ABSTRACT: In the last years scientific community has been witness of the growing interest in global EHF satellite systems for broadband communications; these systems can help national and regional telecommunications service operators to provide broadband communications in areas not adequately served by terrestrial systems. In this paper main EHF satellite missions are presented, outlining challenges and future perspectives.
Antennas and Propagation, 2009. EuCAP 2009. 3rd European Conference on; 04/2009
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T. Rossi, E. Cianca,
M. Lucente,
M. De Sanctis,
C. Stallo,
M. Ruggieri,
A. Paraboni,
A. Vernucci,
L. Zuliani,
L. Bruca,
G. Codispoti
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ABSTRACT: Broadband technologies are taking a predominant role in the emerging information society. In particular, broadband satellite communication systems, with their global access and broadcasting capabilities, are well suited to answer to the requirements of the information society. This paper focuses on the efforts that are currently spent toward the development of EHF (Extremely High Frequency) satellite communications systems. In particular, Q/V (35-75 GHz) and W (75-110 GHz) bands, represent an almost ldquofreerdquo spectrum resource that could be used to realize the so-called satellite gigabit-connectivity, in order to support innovative broadband applications. This paper presents the most important features of an experimental Q/V band satellite network based on the Alphasat TDP#5 (technology demonstration payload), an ongoing project, funded by the Italian space agency, that aims at carrying out communication and propagation experiments over a Q/V band satellite link.
Aerospace conference, 2009 IEEE; 04/2009
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ABSTRACT: The possibility to transfer huge amount of data in a very short time via satellite is attractive both for civil (i.e. telemedicine, tele-learning) and military applications. The use of EHF frequency bands is a viable possibility to reach this objective, even if, especially for the W-band, many challenges arise. The Italian Space Agency has invested in that direction with the conviction that will bring a lot of benefits to both the scientific and industrial community. This paper presents the main experimental missions that have been conceived for the exploitation of EHF frequency bands in communication via satellite.
GLOBECOM Workshops, 2008 IEEE; 01/2009
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ABSTRACT: Q/V band frequencies are expected to play a key role in enabling challenging and unproven broadband communications missions for a wide range of applications. In the perspective to exploit these frequencies, several satellite missions have been proposed to explore the physics of the satellite channel. The strategic importance of probing higher and higher frequencies has been recognized by the Italian Space Agency through the ITALSAT mission that up to date has been the major contributor to the advancement of the Q/V band propagation knowledge. In 2004 ASI funded a feasibility study (phase A study), called TRANSPONDERS, Italian acronym for "research, analysis and study of Q/V payloads for telecommunications", whose main objectives were the improvement of the knowledge of propagation impairments at Q/V band and the evaluation of the effectiveness of PIMTs (Propagation Impairment Mitigation Techniques) in very high frequency band operation. In this paper, after an overview of the potential applications in Q/V band and the top level mission architecture relative to the selected applicative mission at these frequencies, the applicability of three selected PIMTs, such as site diversity, power control and Adaptive Coding and Modulation (ACM), in a Q/V band scenario is discussed and main challenges and key issues are identified.
GLOBECOM Workshops, 2008 IEEE; 01/2009
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ABSTRACT: UWB technology is an attractive technology for Wireless Body Area Networks. There are many advantages of using ultra-wideband (UWB) as both a sensing and a communication standard for biomedical applications: very low radiated power (-41.3 dBm/MHz), low power consumption, good coexistence with other existing wireless technologies, robustness to interference and multipath. Moreover, one specific UWB technology, namely Frequency Modulated (FM)-UWB, has also an important advantage, which make it even more convenient for biomedical applications, such as lower power consumption than IR-UWB. The main issue that is addressed in this paper is the integration of sensing and communication devices using FM-UWB so that a single device can be obtained for two different operational modes. A preliminary feasibility study shows that an integrated sensing and communication device based on FM-UWB can meet the requirements, both for the sensing and the communication points of view, of typical biomedical applications such as non-invasive heart rate monitoring.
Applied Sciences on Biomedical and Communication Technologies, 2008. ISABEL '08. First International Symposium on; 11/2008
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ABSTRACT: It is recognized that W band will be one of the frontier of satellite communications. Pioneering work on the scientific testing of high frequency satellite communications have been DAVID (data and video interactive distribution) mission and WAVE (W band analysis and verification) project, both of them funded by the Italian Space Agency (ASI). The WAVE project was a feasibility study carried out in 2004 for the design and development of a W band geostationary payload. However, a key step towards the exploitation of the W band is the channel characterization. So far, there are no experimental works on W band channel characterization because of the pioneering state of W band communications. This characterization is one of the objective of the second phase of the WAVE project (funded by ASI, started in March 2007) and it will be carried out through two demonstrative missions: 1. mission #1: a payload embarked on a high altitude platform (HAP), Aero-WAVE mission; 2. mission #2: a payload embarked on a LEO nano platform, IKNOW (in-orbit key-test and validation of W band) mission. In this paper, an overview of the first demonstrator, Aero-WAVE, will be outlined on the basis of the preliminary results obtained within phase A2 of WAVE project.
Aerospace Conference, 2008 IEEE; 04/2008
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ABSTRACT: The increasing needs of European observation and telecommunication satellite services, with respect to operations efficiency, require the development of an advanced in-orbit infrastructure for data relay services. The function of a data relay satellite is to forward data between two elements with which it has established a direct communication link. Currently the infrastructure is based on the ESA ARTEMIS satellite that has been operative since 2003 and that will be at end-of-life by the end of 2010. In this frame Thales Alenia Space Italia (TAS-I) and University of Rome "Tor Vergata" (TOR) are conceiving the new European Second Generation Data Relay Satellite System (E2GDRSS) based on state of the art and innovative space technologies and telecommunication techniques. This paper presents the main design options according to preliminary trade-off analysis, which will represent the baseline to the design of the full system.
Aerospace Conference, 2008 IEEE; 04/2008
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ABSTRACT: This paper presents the payload design for an in orbit test of W band technology called IKNOW mission (In orbit Key-test and validatioN Of W band). The increasing demand for frequency bands with large bandwidth availability to satisfy satellite communications applications requirements renders mandatory the need to explore higher and higher frequency ranges. W band (75-110 GHz) could represent the answer to these needs due to the large bandwidth availability, allowing to propose many innovative services that need high-volume transfers. Therefore, the exploitation of W band is foreseen in order to meet the high-quality data transmission for a large number of end users and data-oriented services. The IKNOW mission is a demonstrative experiment foreseen within the phase A2 of the WAVE (W band analysis and verification) project, a study funded by the Italian Space Agency (ASI), which aims at designing and developing W band payloads for telecommunication applications. This paper will be focused on the characterization of the IKNOW mission within the WAVE project devoted to carry out a preliminary channel propagation assessment. Specifically, special attention will be paid to the payload design, particularly critical from the technological point of view at these high frequencies. The basic idea is to develop the receiving/transmitting chain using MMIC devices, in order to fit cost, power and weight constraints, typically limited for a spacecraft. Technological critical items will be highlighted, focusing on the present state of the art and presenting some architectural choices. Moreover, some simulations based on ADS software will be reported in order to simulate the performance of the identified payload configuration.
Aerospace Conference, 2008 IEEE; 04/2008
