Channel equalization for indoor lighting communications networks

We consider indoors communications networks using modulated LEDs to transmit the information packets. A generic indoor channel equalization formulation is proposed assuming the existence of both line of sight and diffuse emitters. The proposed approach is of relevance to emergent indoors distributed sensing modalities for which various lighting based network communications protocols are considered

Terahertz communications for 5G and beyond

A brief discussion about the exclusive properties and applications of terahertz technology is provided in this chapter. The frequency spectrum terahertz (THz) is also discussed. The applications of terahertz in the field of sensors and terahertz for communications are covered. State-of-the-art literature starting from the early to the latest research conducted is provided and analyzed in terms of the performance of terahertz systems. Terahertz, known as Tera waves or T-waves rather than submillimeter wave, has approximately a fraction of a wavelength less than 30 μm. T-wave is heavily used in sensing and imaging applications, and has no ionization hazards and is an excellent candidate frequency band to defeat the multipaths interference problems for pulse communications. The lower quantum energy of T-waves identifies its potential applications toward near-field imaging, telecommunications, spectroscopy, and sensing, including medical diagnoses and security screening. Identification of DNA signatures including complex real-time molecular dynamics through dielectric resonance is a good example of terahertz spectroscopy instruments nowadays. This concluding chapter will not only address the practical applications of terahertz communications, but also identify the research challenges that lie ahead in terms of terahertz antenna desig

Channel sounding and indoor radio channel characteristics in the W-band

This work presents directional radio channel measurements in the W-band using a commercial versatile channel sounder based on a vector network analyzer (VNA), capable of measuring scattering parameters from 75 to 500 GHz with frequency converters. The commercial setup has been modified by increasing the distance for one of the converters using precision coaxial cables and avoiding the use of amplifiers. Firstly, initial distance-dependent single-input single-output (SISO) measurements of indoor radio channels are presented to assess the validity of the setup in the 75 110 GHz frequency band with highly directive horn antennas. Then, single-input multiple-output (SIMO) radio channels were measured at 94 GHz using one directional and one omnidirectional antenna mounted on two positioners. Initial channel characterization is presented comprising root mean square (rms) delay spread, rms angular spread, K-factor, and path loss in an indoor environment at 94 GHz.This work was supported by MINECO, Spain (TEC2013-47360-C3-2-P TEC2013-47360-C3-3-P) and by European FEDER funds.Martínez Inglés, M.; Gaillot, D.; Pascual-García, J.; Molina-García-Pardo, JM.; Rodriguez Rodriguez, JV.; Rubio Arjona, L.; Juan Llacer, L. (2016). Channel sounding and indoor radio channel characteristics in the W-band. EURASIP Journal on Wireless Communications and Networking. 30:1-8. doi:10.1186/s13638-016-0530-7S1830D Zico, Ultra-wideband and 60 GHz communications for biomedical applications. Springer. http://link.springer.com/book/10.1007%2F978-1-4614-8896-5 .L Jofre, J Romeu, S Capdevila, J Abril, E Nova, M Alonso, The “challenging” world of Terahertz radiation and imaging. Proceedings of the 5th European Conference on Antennas and Propagation (EUCAP), 2011, pp. 3470–3475M Kawase, “Non-destructive evaluation method of pharmaceutical tablet by terahertz-time-domain spectroscopy: application to sound-alike medicines”, J. Infrared Millimeter Terahertz Waves, 34(9), 566–571KD Anderson, 94 GHz propagation in the evaporation duct. IEEE Trans. Antennas Propag. 38(5), 746–753 (1990)K Aydin, Y-M Lure, Millimeter wave scattering and propagation in rain: a computational study at 94 and 140 GHz for oblate spheroidal and spherical raindrops. IEEE Trans. Geosci. Remote Sens. 29(1), 593–601 (1991)C Gloaguen, An experiment for propagation studies at 94 GHz. Eighth Int. Conf. Antennas Propagation 1, 406–409 (1993)A Kajiwara, “Indoor propagation measurements at 94 GHz,” personal, indoor and mobile radio communications, 1995. Sixth IEEE Int. Symp PIMRC’95. Wireless Merging Inf. Superhighway 3, 1026 (1995)J Helminger, J Detlefsen, H Groll, Propagation properties of an indoor-channel at 94 GHz. Int. Conf. Microw Millimeter Wave Technol.Proc 98, 9–14 (1998)R Piesiewicz, R Geise, M Jacob, J Jemai, T Kurner, “Indoor channel measurements of point-to-point ultra broadband short range links between 75 GHz and 110 GHz”, in International Symposium Antennas and Propagation Society, 2008, pp. 1–4A Brizzi, A Pellegrini, Y Hao, “Experimental characterization of the propagation on the human torso at W band”, in Radio Science Meeting (Joint with AP-S Symposium), USNC-URSI, 2013, p. 39K Haneda, J Järveläinen, A Karttunen, M Kyro, J Putkonen, Indoor short-range radio propagation measurements At 60 and 70 GHz, in EuCAP 2014, The Hague, The Netherlands, 2014, pp. 1–4S Promwong, J Takada, Free space link budget estimation scheme for ultra wideband impulse radio with imperfect antennas. IEICE Electronics Express 1(7), 188–192 (2004)NL Johnson, S Kotz, N Balakrishnan, Continuous univariate distributions, vol. 1 (Wiley-Interscience, Hoboken, 1993)A Richter, Estimation of radio channel parameters: models and algorithms (Dr.-Ing. dissertation, TU Ilmenau, Ilmenau, Germany, 2005

Effect of sitagliptin on cardiovascular outcomes in type 2 diabetes

BACKGROUND: Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin, a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2 diabetes and cardiovascular disease. METHODS: In this randomized, double-blind study, we assigned 14,671 patients to add either sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic therapy was encouraged as required, aimed at reaching individually appropriate glycemic targets in all patients. To determine whether sitagliptin was noninferior to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. RESULTS: During a median follow-up of 3.0 years, there was a small difference in glycated hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo, -0.29 percentage points; 95% confidence interval [CI], -0.32 to -0.27). Overall, the primary outcome occurred in 839 patients in the sitagliptin group (11.4%; 4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per 100 person-years). Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P = 0.98). There were no significant between-group differences in rates of acute pancreatitis (P = 0.07) or pancreatic cancer (P = 0.32). CONCLUSIONS: Among patients with type 2 diabetes and established cardiovascular disease, adding sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular events, hospitalization for heart failure, or other adverse events

High efficiency single-phase line start PMSM with number of poles 2p= 4 – experimental results

The paper presents a comparison of selected running properties of a prototype, single-phase synchronous motor with permanent magnets with a corresponding induction motor (the same dimensions and the same number of poles). In experimental studies performed on a specially adapted test bench the mechanical construction of the stator of the series production motor was used

Time divisional and time-frequency divisional cooperative spectrum sensing

In this paper we present a time divisional and a time-frequency divisional cooperative spectrum sensing technique suitable for cognitive radio (CR) networks. The two methods are well suited for very high bandwidth CR networks, such as UWB networks, where the individual nodes need to scan a wide range of spectrum which is a time consuming process. With the time divisional and the time-frequency divisional cooperative spectrum sensing approaches the nodes share the spectrum sensing functions cooperatively, coordinating in time and frequency, covering the total frequency band and also in near-continuous time. In this paper we present the corresponding algorithms and techniques for the two cooperative spectrum sensing approaches, analyze their performances, and compare the advantages and disadvantages with each other. We also present simulation results to verify the performance improvements in terms of probability of miss detection and the probability of false alarm for detecting the PU. Results show that the the proposed methods are best suited for detecting the PUs having low spectral occupancy statistics who occupy the spectrum very seldom

Cooperative shared spectrum sensing for dynamic cognitive radio network

Cooperative spectrum sensing for cognitive radio networks is recently being studied to simultaneously minimize uncertainty in primary user detection and solve hidden terminal problem. Sensing wideband spectrum is another challenging task for a single cognitive radio due to large sensing time required. In this paper, we introduce a technique to tackle both wideband and cooperative spectrum sensing tasks. We divide the wideband spectrum into several subbands. Then a group of cognitive radios is assigned for sensing of a particular narrow subband. A cognitive base station is used for collecting the results and making the final decision over the full spectrum. Our proposed algorithm minimizes time and amount of energy spent for wideband spectrum scanning by a cognitive radio, and effectively detects the primary users in the wideband spectrum thanks to cooperative shared spectrum sensing

Spectrum sensing for cognitive radios with transmission statistics: Considering linear frequency sweeping

The spectrum sensing performance of Cognitive Radios (CRs) considering noisy signal measurements and the time domain transmission statistics of the Primary User (PU) is considered in this paper. When the spectrum is linearly swept in the frequency domain continuously to detect the presence of the PU the time-domain statistics of the PU plays an important role in the detection performance. This is true especially when the PU&#039;s bandwidth is much smaller than the CR&#039;s scanning frequency range. We model the transmission statistics that is the temporal characteristics of the PU as a Poisson arrival process with a random occupancy time. The spectrum sensing performance at the CR node is then theoretically analyzed based on noisy envelope detection together with the time domain spectral occupancy statistics. The miss detection and false alarm probabilities are derived from the considered spectral occupancy model and the noise model, and we present simulation results to verify our theoretical analysis. We also study the minimum required sensing time for the wideband CR to reliably detect the narrowband PU with a given confidence level considering its temporal characteristics

Hybrid control plane architecture for dynamic impairment-aware routingin transparent optical networks

We propose a hybrid control plane architecture, in which both RSVP-TE and OSPF-TE are extended to carry PLIs information and disseminate wavelength availability information, respectively, for impairment-aware routing in transparent optical networks. The results suggest that, hybrid approach provides good trade-off between control overhead and network performance

Impairment aware GMPLS-based control plane architectures to realize dynamically reconfigurable transparent optical networks

Standard GMPLS protocols used for dynamic establishment of lightpaths in transparent optical networks suffer from lack of physical layer impairments (PLIs) information, which makes it difficult to evaluate optical feasibility. In this paper, we compare two impairment aware (IA)-GMPLS architectures: signalling based-in which RSVP-TE is extended to carry PLIs and hybrid architecture-in which RSVP-TE and OSPF-TE are extended to carry PLIs and wavelength availability information, respectively. We show that it is sufficient to extend OSPF-TE to disseminate wavelength availability information, while RSVP-TE carries PLIs to validate the optical feasibility and to achieve trade-off between performance and control overhead