Spectral and power efficiency trade-offs for multiple-antenna reception techniques under co-channel interference

2011 ◽  
Vol 22 (7) ◽  
pp. 415-427 ◽  
Author(s):  
Özgür Ertuğ
Technologies ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 22
Author(s):  
Ramiro Sámano-Robles

This paper investigates backlog retransmission strategies for a class of random access protocols with retransmission diversity (i.e., network diversity multiple access or NDMA) combined with multiple-antenna-based multi-packet reception (MPR). This paper proposes NDMA-MPR as a candidate for 5G contention-based and ultra-low latency multiple access. This proposal is based on the following known features of NDMA-MPR: (1) near collision-free performance, (2) very low latency values, and (3) reduced feedback complexity (binary feedback). These features match the machine-type traffic, real-time, and dense object connectivity requirements in 5G. This work is an extension of previous works using a multiple antenna receiver with correlated Rice channels and co-channel interference modelled as a Rayleigh fading variable. Two backlog retransmission strategies are implemented: persistent and randomized. Boundaries and extended analysis of the system are here obtained for different network and channel conditions. Average delay is evaluated using the M/G/1 queue model with statistically independent vacations. The results suggest that NDMA-MPR can achieve very low values of latency that can guarantee real- or near-real-time performance for multiple access in 5G, even in scenarios with high correlation and moderate co-channel interference.


2018 ◽  
Vol 2018 ◽  
pp. 1-12
Author(s):  
Nathan A. Tehrani ◽  
Jason N. Gross

We present various performance trades for multiantenna global navigation satellite system (GNSS) multisensor attitude estimation systems. In particular, attitude estimation performance sensitivity to various error sources and system configurations is assessed. This study is motivated by the need for system designers, scientists, and engineers of airborne astronomical and remote sensing platforms to better determine which system configuration is most suitable for their specific application. In order to assess performance trade-offs, the attitude estimation performance of various approaches is tested using a simulation that is based on a stratospheric balloon platform. For GNSS errors, attention is focused on multipath, receiver measurement noise, and carrier-phase breaks. For the remaining attitude sensors, different performance grades of sensors are assessed. Through a Monte Carlo simulation, it is shown that, under typical conditions, sub-0.1-degree attitude accuracy is available when using multiple antenna GNSS data only, but that this accuracy can degrade to degree level in some environments warranting the inclusion of additional attitude sensors to maintain the desired level of accuracy. Further, we show that integrating inertial sensors is more valuable whenever accurate pitch and roll estimates are critical.


2017 ◽  
Vol 13 (4) ◽  
pp. 345-369
Author(s):  
Kamel Barka ◽  
Azeddine Bilami ◽  
Samir Gourdache

Purpose The purpose of this paper is to ensure power efficiency in wireless sensor networks (WSNs) through a new framework-oriented middleware, based on a biologically inspired mechanism that uses an evolutionary multi-objective optimization algorithm. The authors call this middleware framework multi-objective optimization for wireless sensor networks (MONet). Design/methodology/approach In MONet, the middleware level of each network node autonomously adjusts its routing parameters according to dynamic network conditions and seeks optimal trade-offs among performance objectives for a balance of its global performance. MONet controls the cooperation between agents (network nodes) while varying transmission paths to reduce and distribute power consumption equitably on all the sensor nodes of network. MONet-runtime uses a modified TinyDDS middleware platform. Findings Simulation results confirm that MONet allows power efficiency to WSN nodes while adapting their sleep periods and self-heal false-positive sensor data. Originality/value The framework implementation is lightweight and efficient enough to run on resource-limited nodes such as sensor nodes.


2014 ◽  
Vol 62 (1) ◽  
pp. 59-73 ◽  
Author(s):  
Yuzhen Huang ◽  
Fawaz Al-Qahtani ◽  
Caijun Zhong ◽  
Qihui Wu ◽  
Jinlong Wang ◽  
...  

Author(s):  
Juan David Diazgranados-Garzón ◽  
Juan Camilo Romero-Bravo ◽  
Loraine Isabel Navarro-Estrada ◽  
Rafael De Jesús Castillo-Sierra ◽  
Jose Daniel Soto-Ortiz ◽  
...  

This paper summarizes the impact of particulate material on solar-panel performance for systems located in the Colombian Caribbean Region. First, the dirt/particles are identified and classified; and then, their effect in the reduction of solar panel efficiency has been estimated at most of 6% during the times of the day with the maximum solar radiation. It has been found that the impact decreases exponentially for other hours during the day, which implies that dirt effect becomes negligible on the electric power available. The study reveals that the effect of dirt/particles is significant from a clean solar panel to one with light accumulation, but rapidly diminishes as accumulation changes from light to heavy. Thus, it is suggested that once some dirt accumulates on the panel, a cleaning procedure can wait until the particle accumulation is heavy without sacrificing efficiency excessively. The results of the study become a tool to estimate the trade-offs between power efficiency of photovoltaic systems and financial viability of those projects. Hence, inverters can be chosen such that they can limit the amount of electric power while minimizing the stochastic nature of solar radiation and the dirt/particle effect. The analysis presented starts through a complete Multivariate Analysis of Variance (ANOVA) considering three fundamental factors: dirt/particles, solar radiation and day.


Author(s):  
Ulla Slothuus ◽  
Mette L. Larsen ◽  
Peter Junker

Objective: To compare two methods of measuring willingness to pay (WTP): closed-ended questions with and without follow-up.Methods: A measurement experiment based on dichotomous choice contingent valuation survey data is reported. Marginal WTP estimates for alleviation of rheumatoid arthritis symptoms resulting from treatment with a novel anti-rheumatic agent, cA2 (TNF-α blockade), were calculated. Monte Carlo simulations were undertaken to evaluate the methods with respect to their statistical power.Results: The estimated marginal WTP values using closed-ended questions with and without follow-up were DKK 637 (US $91) and DKK 1,268 (US $181), respectively. A Wilcoxon's signed-rank test showed that the difference of DKK 631 was significant. Moreover, including a follow-up question increases the precision of the result. Monte Carlo simulations showed that trade-offs between power (i.e., the probability of a correct rejection of a false null hypothesis), efficiency, and size may exist in the two models.Conclusions: There was a significant difference between the WTP estimates when using closed-ended questions with and without follow-up. When choosing between the models, however, power, efficiency, and size could be used as selection criteria.


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