| 1. |
- Afey Ali Zaidi, Zyed, et al.
(author)
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Waveform and Numerology to Support 5G Services and Requirements
- 2016
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In: IEEE Communications Magazine. - : IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. - 0163-6804 .- 1558-1896. ; 54:11, s. 90-98
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Journal article (peer-reviewed)abstract
- The standardization of the next generation 5G radio access technology has just started in 3GPP with the ambition of making it commercially available by 2020. There are a number of features that are unique for 5G radio access compared to the previous generations such as a wide range of carrier frequencies and deployment options, diverse use cases with very different user requirements, small-size base stations, self-backhaul, massive MIMO, and large channel bandwidths. In this article, we propose a flexible physical layer for the NR to meet the 5G requirements. A symmetric physical layer design with OFDM is proposed for all link types, including uplink, downlink, device-to-device, and backhaul. A scalable OFDM waveform is proposed to handle the wide range of carrier frequencies and deployments.
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| 2. |
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| 3. |
- Bourdoux, Andre, et al.
(author)
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D1.2 MaMi Channel Characteristics: Measurement Results
- 2015
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Reports (other academic/artistic)abstract
- This deliverable presents channel measurement results for the scenariosOpen exhibition and Crowded auditiorium. The measurement procedureand equipment are described. Massive MIMO (MaMi) channel characteristicsand key parameters are extracted and used in an extended COST 2100channel model for MaMi. The initial validation performed shows that themodel is capable of reproducing the statistics in terms of temporal behaviorof the user separability, singular value spread, capacity and sum-rate anddirectional characteristics. The model can be used for system and link levelMaMi simulations.
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| 4. |
- Hanson, Robin, 1981, et al.
(author)
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Manual picking from flat and tilted pallet containers
- 2018
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In: International Journal of Industrial Ergonomics. - : Elsevier BV. - 1872-8219 .- 0169-8141. ; 64, s. 199-212
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Journal article (peer-reviewed)abstract
- Manual picking operations commonly occur both in distribution settings and within manufacturing industry and may consume large proportions of the working day for operators, with associated potential problems of poor postural ergonomics and low time efficiency. As a remedy to such problems, alternative material layouts like tilted material pallets may be an attractive solution. This study provides quantitative empirical evidence comparing the relative merits and drawbacks of flat and tilted pallet configurations, with regard to physical ergonomic loading and time consumption. This was explored with an experimental setup at the site of an industrial company, where various representative picking operators were observed while emptying flat and tilted pallets. The observation was video recorded and subjected to a time study and Rapid Entire Body Assessment (REBA). Results showed that there are differences in picking time and physical workload depending on where in the pallet the picking action takes place, and that flat and tilted pallets bring different postural opportunities and challenges for different operator percentiles in the working population. An overview of postural ergonomics consequences and their associated risk levels are shown, and the results serve to further increase the understanding of which factors are affected by choosing between a tilted or flat component presentation. This understanding is highly relevant to industry, where it can contribute to the design of both efficient and ergonomically sound processes for manual picking operations.
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| 5. |
- Harrysson, Fredrik, et al.
(author)
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Efficient experimental evaluation of a MIMO handset with user influence
- 2010
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In: IEEE Transactions on Wireless Communications. - 1536-1276. ; 9:2, s. 853-863
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Journal article (peer-reviewed)abstract
- The immediate environment of handset antennas, including the casings and the users holding the handsets, has a strong impact on the radio channel in mobile communication. In this paper we investigate a composite channel method that synthetically combines double-directional measurements of the userless propagation channel with measured super-antenna patterns, i.e., patterns of the combined antenna-casing-user arrangement. We experimentally evaluate the method by comparing results (power, capacity, and eigenvalue distribution) obtained from this composite method with direct measurements in the same environment. The measurements were done in two static 8 × 4 MIMO scenarios at 2.6 GHz, with the user indoors and the base station located outdoors and indoors, respectively. A realistic user phantom together with a “smart-phone” handset mock-up with four antenna elements was used, and different configurations and orientations were tested. The method gives statistical distributions of the MIMO eigenvalues, that are close to the measured. By using the composite method, we found that the user, apart from introducing hand and body loss that mainly decreases the SNR of the channel, slightly increases the correlation between the fading at the antenna elements.
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| 6. |
- Harrysson, Fredrik, et al.
(author)
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Experimental Investigation of the Directional Outdoor-to-In-Car Propagation Channel
- 2013
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In: IEEE Transactions on Vehicular Technology. - 1939-9359. ; 62:6, s. 2532-2543
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Journal article (other academic/artistic)abstract
- Abstract in UndeterminedThe demand for wireless channel models including realistic user environments is increasing. This motivates work on more detailed models that are reasonably simple and tractable but with adequatestatistical performance. In this paper, we present an investigation of the spatial outdoor-to-in-car radio channel at 2.6 GHz. Specifically, we investigate the performance of a multiple antenna smartphone mockup in the hand of a user. We evaluate and utilize a composite channel approach to combine measured antenna radiation patterns with an estimated spectral representation of the multipath channel outside and inside the car in two different scenarios. The performance of the method is investigated and comparisons with direct channel measurements are performed. Statistical and directional properties of the outdoorto-in-car channel are presented and analyzed. It is found that the composite method, despite nearfieldproblems when estimating plane-wave channel parameters in a very narrow environment, constitutes a tool that provides reasonably viable statistical results. In addition, we have found that the introduction of the car in the propagation environment increases scattering and eigenvalue dispersion while it decreases pairwise antenna signal correlation. These statistical properties are found to slightly increase the possible diversity and the spatial multiplexing gains of multiple antenna terminals when located inside cars. Thispositive effect, however, is small compared to the negative effect of car penetration loss.
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| 7. |
- Harrysson, Fredrik, et al.
(author)
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The composite channel method : Efficient experimental evaluation of a realistic MIMO terminal in the presence of a human body
- 2008
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In: 2008 IEEE 67th Vehicular Technology Conference-Spring, VTC. - 1550-2252. - 9781424416455 ; , s. 473-477
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Conference paper (peer-reviewed)abstract
- The immediate environment of the transmit (TX) and receive (RX) antennas, including the antenna casings and the users holding the antennas, has a strong impact on the propagation channel and thus on wireless systems. In this paper we experimentally evaluate a method that synthetically combines double-directional measurements of the propagation channel (without the user influence) with measured antenna patterns of antennas-plus-users, by comparing obtained sample results with direct measurements in the same environment. The measurements are done for a static microcell 8×4 MIMO scenario at 2.6 GHz. A realistic user phantom was used together with a test terminal prototype with four antenna elements, and a number of different configurations and orientations of the phantom were tested. In average over all test cases, the mean signal power deviation between composite channel method and measurements was well within 1 dB. The composite method shows 6% higher terminal antenna correlation but similar statistical distributions as the measured. The differences between the model and measurements for the strongest eigenvalue (relevant for MRC combining) was found to be within 1 dB above 10% outage level. Relative deviations in the ergodic MIMO capacity were smaller than 10%.
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| 8. |
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| 9. |
- Jensen, Michael Allen, et al.
(author)
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Performance of cooperative MIMO based on measured urban channel data
- 2011
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In: Proceedings of the 5th European Conference on Antennas and Propagation (EUCAP). - 9781457702501 - 9788882020743
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Conference paper (peer-reviewed)abstract
- We study the potential benefits of cooperative multiple-input multiple-output signaling from multiple coherent base stations with one or more mobile stations in an urban macrocellular environment. The analysis uses novel and fully coherent measurements of the channel from three base stations to a single mobile station equipped with four antennas. The observed channels are used to explore the gains in capacity enabled by cooperative base station signaling for point-to-point and multi-user communications. The analysis shows that cooperative signaling using practical algorithms yields significant increases in average capacity.
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| 10. |
- Lau, Buon Kiong, et al.
(author)
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Downlink cooperative MIMO in urban macrocell environments
- 2010
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In: 2010 IEEE Antennas and Propagation Society International Symposium (APSURSI). - 9781424449675
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Conference paper (peer-reviewed)abstract
- In this paper, we study the potential benefits of downlink cooperative MIMO systems in cellular macrocell environments using a coherent measurement setup. Our results reveal that one of the two measured routes can leverage comparable signal strengths from the cooperating base stations to the mobile station and provide up to two-fold single user bitrate gain at the 50% cumulative probability level
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| 11. |
- Lau, Buon Kiong, et al.
(author)
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Single and multi-user cooperative MIMO in a measured urban macrocellular environment
- 2012
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In: IEEE Transactions on Antennas and Propagation. - 0018-926X. ; 60:2, s. 624-632
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Journal article (peer-reviewed)abstract
- We study the potential benefits of cooperative multiple-input multiple-output signaling from multiple coherent base stations with one or more mobile stations in an urban macrocellular environment at 2.66 GHz. The analysis uses fully-coherent measurements of the channel from three base stations to a single mobile station equipped with four antennas. The observed channels are used to explore the gains in capacity enabled by cooperative base station signaling for point-to-point and multiuser communications. The analysis shows that for point-to-point links, the average capacity for cooperative signaling is 53% higher than that achieved for a single base station. For downlink and uplink communication with three mobile users, cooperative signaling using practical algorithms yields average sum rate increases of 91% and 63%, respectively.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Medbo, Jonas, et al.
(author)
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Temporal radio channel variations with stationary terminal
- 2004
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In: [Host publication title missing]. - 1090-3038. - 0780385217 ; 1, s. 91-95
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Conference paper (peer-reviewed)abstract
- In wireless communications, stationary terminal scenarios are becoming increasingly important as bitrates goes up. Consequently, the need to improve the knowledge about the channel behavior and to develop realistic channel models for these scenarios is also increasing. The present work comprises both measurements and modeling of the radio channel when the terminal is stationary. The measurements were performed at 5 GHz in indoor scenarios using a vector network analyzer. The measured channel was essentially static most of the time. Only about 1% of the time did it show substantial channel variations. An important finding is that the dominant cause for temporal channel variations in the measurements was the movement of persons in the vicinity of either antenna. This is also supported by a simple model, based on a single moving scatterer, which shows good agreement with measurements.
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| 16. |
- Renström, Jonas
(author)
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Senior Managers and Lean- The importance of becoming a practitioner
- 2014
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Licentiate thesis (other academic/artistic)abstract
- Considered to be one of the most influential paradigms in manufacturing, Lean has developed and expanded beyond the shop floor and manufacturing environment of the auto industry. Lean is considered to be applicable throughout organizations and other industries besides manufacturing. Interest in both research and implementation of the Lean concept, heavily influenced by Toyota Motor Company, is said to continue to increase despite the fact that the concept is said to be both ambiguous and difficult to implement. Two main traditions of Lean are said to exist: “toolboxLean” and “Lean thinking.” The particular translation of the concept that is accepted will influence management’s approach in implementing a Lean way of working. The Toyota Motor Company, where Lean originates, is described as a learning organization. Therefore, a management approach and leader behavior supporting organizational learning would be required to successfully implement an enterprise system inspired by both the Toyota Production System and Lean. This thesis approaches the Lean concept through an organizational learning perspective, thereby highlighting the importance of knowledge of organizational learning in a Lean development effort. Difficulties regarding Lean implementations have been shown to often occur due to the overlooked but crucial differences in approach in management. There is, however a stated gap in the literature on Lean production regarding management. The purpose of this thesis is to explore senior management’s ability to implement and sustain a Lean-based enterprise system. Three studies are included in the thesis. The first study focuses on how the view on Lean among managers implementing Lean affects its implementation. The study was performed as a case study and conducted at a larger, international manufacturing company. The study covered management levels from shop floor manager to the president of the company. Findings show that all management levels had a similar view of Lean and that this influenced the implementation. The first study further showed that the view on Lean may develop and change during an implementation, revealing unforeseen managerial and organizational challenges and obstacles.The second study focused on how management of Lean is described in the existing literature. The results revealed a dualistic complementarity between leadership and management, which can be seen as reflected in the two foundational Toyota principles of continuous improvement and respect for people. This duality can also be found in descriptions of prerequisites for organizational learning where the ability to combine transactional and transformational leadership is considered a success factor. The third study focused on implications for senior management and aimed to research senior managers’ ability to support a Lean implementation process. The study is based on interviews with eight senior managers. The study revealed four main managerial obstacles to Lean implementation. Lack of initial competence evaluation and ensuing competence development for senior management was found to be a central obstacle to Lean implementation. Main conclusions in the thesis are that initial understanding of the aims of a Lean implementation, and the ensuing implications for the organization is central in order to be able to support the development. Additionally, initial senior management competence development is indicated to be vital in order to ensure the ability to understand the organizational and managerial implications brought on by a Lean implementation. Leading with action is indicated as providing an opportunity for senior management competence development.
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| 17. |
- Riback, Mathias, et al.
(author)
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Carrier frequency effects on path loss
- 2006
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In: [Host publication title missing]. - 1550-2252. ; 6, s. 2717-2721
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Conference paper (peer-reviewed)abstract
- To study the carrier frequency effects on path loss, measurements have been conducted at four discrete frequencies in the range 460-5100 MHz. The transmitter was placed on the roof of a 36 meters tall building and the receive antennas were placed on the roof of a van. Both urban and suburban areas were included in the measurement campaign. The results show that there is a frequency dependency, in addition to the well known free-space dependency 20 log10(f), in most of the areas included in the measurements. In non line of sight conditions, the excess path loss is clearly larger at the higher frequencies than at the lower. A model capturing these effects is presented
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| 18. |
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| 19. |
- Tian, Ruiyuan, et al.
(author)
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On capacity improvement using multisector cooperative MIMO in a real urban macrocellular environment
- 2012
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Conference paper (other academic/artistic)abstract
- For the first time, the capacity gain of multisector cooperative multiple-input multiple-output(MIMO) using all three 120 degree sectors of a base station (BS) site is studied in a measured urban macrocellular environment at 2.65GHz. The results reveal that the mean uplink capacity gain exceeds 40% in as much as 1/4 of the coverage area, relative to the best single-sector link with no cooperation. Moreover, a simple simulation model is developed for predicting the capacity gain from the multisector cooperation. The model is used to determine the respective roles of the BS antenna patterns and propagation mechanisms in the cooperative performance.
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| 20. |
- Tian, Ruiyuan, et al.
(author)
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On MIMO performance enhancement with multi-sector cooperation in a measured urban environment
- 2012
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In: IEEE Antennas and Wireless Propagation Letters. - 1548-5757. ; 11, s. 488-491
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Journal article (peer-reviewed)abstract
- Capacity improvement of intrasite cooperative MIMO using all three 120 degree-sectors of a base station (BS) site is studied for the first time in a measured urban environment at 2.65GHz. The results show that the mean uplink capacity gain exceeds 40% in as much as 1/4 of the coverage area, relative to the best single-sector link with no cooperation. In addition, a simple simulation model is developed for predicting the capacity gain from intrasite multi-sector cooperation. The model is used to unravel the respective roles of the BS antenna patterns and propagation mechanisms in determining cooperative performance.
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| 21. |
- Tian, Ruiyuan, et al.
(author)
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On the orthogonality of dual-polarized channels with Rician fading
- 2012
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Conference paper (other academic/artistic)abstract
- Abstract in UndeterminedIn this paper, the orthogonality of dual-polarized MIMO channels with Rician fading is investigated in a measured urban macrocellular scenario. Overall, efficient two-stream MIMO communication can be achieved as more than 70% of the measured route achieves better channel orthogonality than the average performance of the reference IID Rayleigh channel. Furthermore, the study confirms that the Rician K-factors of the co- and cross-polarized channels are strongly correlated to each other. However, strong Rician fading can either enhance or degrade the orthogonality of dual-polarized channels.Our results show that the channel orthogonality depends largely on the co- and cross-polarization ratios of the dual-polarized channel in the presence of strong Rician fading. In particular, good channel orthogonality is achieved when the co-polarization ratio is close to 1 and the cross-polarization ratio is small, respectively.
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| 22. |
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| 23. |
- Zaidi, Ali Abbas Syed, 1983, et al.
(author)
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5G physical layer: Principles, models and technology components
- 2018
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Book (other academic/artistic)abstract
- 5G Physical Layer: Principles, Models and Technology Components explains fundamental physical layer design principles, models and components for the 5G new radio access technology - 5G New Radio (NR). The physical layer models include radio wave propagation and hardware impairments for the full range of frequencies considered for the 5G NR (up to 100 GHz). The physical layer technologies include flexible multi-carrier waveforms, advanced multi-antenna solutions, and channel coding schemes for a wide range of services, deployments, and frequencies envisioned for 5G and beyond. A MATLAB-based link level simulator is included to explore various design options. 5G Physical Layer is very suitable for wireless system designers and researchers: basic understanding of communication theory and signal processing is assumed, but familiarity with 4G and 5G standards is not required.
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| 24. |
- Zhu, Meifang, et al.
(author)
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Correlation properties of large scale parameters from 2.66 GHz multi-site macro cell measurements
- 2011
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In: [Host publication title missing]. - 1550-2252. - 9781424483327
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Conference paper (peer-reviewed)abstract
- Multi-site measurements for urban macro cells at 2.66 GHz are performed with three base stations and one mobile station. In order to analyze the correlation properties of large scale parameters, we split up the routes into subsets, where it can be assumed that wide-sense stationarity (WSS) applies. The autocorrelation distance and correlation properties of large scale parameters for each link are analyzed. By comparing these properties with the corresponding parameters from the COST 2100 and WINNER II models, we can see that the measured autocorrelation distance of the shadow fading as well the autocorrelation distance of delay spread have similar properties as in the two models. The shadow fading and delay spread from the same link are negatively correlated and match the two models well. Based on the WSS subsets, we can see that large scale parameters for different links can be correlated, also when two BSs are far away from each other. In those cases the correlation of different links tends to be positively correlated when both base stations are in the same direction compared to the movement of the MS, otherwise the two links are usually negatively correlated.
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