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Händel, P. & Ronnow, D. (2018). Dirty MIMO Transmitters: Does It Matter?. IEEE Transactions on Wireless Communications, 17(8), 5425-5436
Open this publication in new window or tab >>Dirty MIMO Transmitters: Does It Matter?
2018 (English)In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 17, no 8, p. 5425-5436Article in journal (Refereed) Published
Abstract [en]

The radio frequency transmitter is a key component in contemporary multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing systems. A detailed study of a 2 x 2 MIMO transmitter subjected to correlated input data streams, nonlinear distortion, thermal noise, and crosstalk is provided by stochastic modeling. The effects of correlated input streams, crosstalk, and nonlinearities are studied in detail and exemplified both by approximate expressions and numerical simulations. Key results include exact and approximate expressions for the normalized mean-squared error (NMSE) for systems with or without digital predistortion; the relationship between NMSE and the signal-to-noise-and-distortion ratio, the properties of the distortion noise, and a novel design for power amplifier back-off for MIMO transmitters subject to crosstalk. The theoretical derivations are illustrated by numerical examples and simulation results, and their relationships to the state-of-the-art research are discussed.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2018
Keywords
Orthogonal frequency division multiplexing (OFDM), input back-off, power amplifier, optimization, Bussgang theory
National Category
Signal Processing
Identifiers
urn:nbn:se:kth:diva-234629 (URN)10.1109/TWC.2018.2843764 (DOI)000441933900034 ()2-s2.0-85048562714 (Scopus ID)
Note

QC 20190913

Available from: 2018-09-13 Created: 2018-09-13 Last updated: 2018-09-13Bibliographically approved
Khan, Z. A., Zenteno, E., Händel, P. & Isaksson, M. (2018). Extraction of the Third-Order 3x3 MIMO VolterraKernel Outputs Using Multitone Signals. IEEE transactions on microwave theory and techniques
Open this publication in new window or tab >>Extraction of the Third-Order 3x3 MIMO VolterraKernel Outputs Using Multitone Signals
2018 (English)In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670Article in journal (Refereed) Epub ahead of print
Abstract [en]

This paper uses multitone signals to simplify theanalysis of 3×3 multiple-input multiple-output (MIMO) Volterrasystems by isolating the third-order kernel outputs from eachother. Multitone signals fed to an MIMO Volterra system yielda spectrum that is a permutation of the sums of the inputsignal tones. This a priori knowledge is used to design multitonesignals such that the third-order kernel outputs are isolated inthe frequency domain. The signals are designed by deriving theconditions for the offset and spacing of the input frequency grids.The proposed technique is then validated for the six possibleconfigurations of a 3x3 RF MIMO transmitter impaired bycrosstalk effects. The proposed multitone signal design is usedto extract the third-order kernel outputs, and their relativecontributions are analyzed to determine the dominant crosstalkeffects for each configuration.

National Category
Signal Processing
Identifiers
urn:nbn:se:kth:diva-233974 (URN)10.1109/TMTT.2018.2854186 (DOI)
Note

QC 20180904

Available from: 2018-09-01 Created: 2018-09-01 Last updated: 2018-09-21Bibliographically approved
Wahlström, J., Skog, I., Nordström, R. L. & Händel, P. (2018). Fusion of OBD and GNSS Measurements of Speed. IEEE Transactions on Instrumentation and Measurement, 67(7), 1659-1667
Open this publication in new window or tab >>Fusion of OBD and GNSS Measurements of Speed
2018 (English)In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 67, no 7, p. 1659-1667Article in journal (Refereed) Published
Abstract [en]

There are two primary sources of sensor measurements for driver behavior profiling within insurance telematics and fleet management. The first is the on-board diagnostics system, typically found within most modern cars. The second is the global navigation satellite system, whose associated receivers commonly are embedded into smartphones or off-the-shelf telematics devices. In this paper, we present maximum likelihood and maximum a posteriori estimators for the problem of fusing speed measurements from these two sources to jointly estimate a vehicle's speed and the scale factor of the wheel speed sensors. In addition, we analyze the performance of the estimators by use of the Cramer-Rao bound, and discuss the estimation of model parameters describing measurement errors and vehicle dynamics. Last, simulations and real-world data are used to show that the proposed estimators yield a substantial performance gain compared to when employing only one of the two measurement sources.

Place, publisher, year, edition, pages
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2018
Keywords
Driver behavior profiling, fleet management, global navigation satellite system (GNSS), insurance telematics, on-board diagnostics (OBD)
National Category
Control Engineering Vehicle Engineering
Identifiers
urn:nbn:se:kth:diva-231179 (URN)10.1109/TIM.2018.2803998 (DOI)000434457600016 ()2-s2.0-85042872129 (Scopus ID)
Note

QC 20180720

Available from: 2018-07-20 Created: 2018-07-20 Last updated: 2018-07-20Bibliographically approved
Amin, S., Landin, P. N., Händel, P. & Rönnow, D. (2017). 2D Extended envelope memory polynomial model for concurrent dual-band RF transmitters. International journal of microwave and wireless technologies, 9(8), 1619-1627
Open this publication in new window or tab >>2D Extended envelope memory polynomial model for concurrent dual-band RF transmitters
2017 (English)In: International journal of microwave and wireless technologies, ISSN 1759-0795, E-ISSN 1759-0787, Vol. 9, no 8, p. 1619-1627Article in journal (Refereed) Published
Abstract [en]

The paper presents a two-dimensional (2D) extended envelope memory polynomial model for concurrent dual-band radio frequency (RF) power amplifiers (PAs). The model is derived based on the physical knowledge of a dual-band RF PA. The derived model contains cross-modulation terms not included in previously published models; these terms are found to be of importance for both behavioral modeling and digital predistortion (DPD). The performance of the derived model is evaluated both as the behavioral model and DPD, and the performance is compared with state-of-the-art 2D-DPD and dual-band generalized memory polynomial (DB-GMP) models. Experimental result shows that the proposed model resulted in normalized mean square error of -51.7/-51.6 dB and adjacent channel error power ratio of -63.1/-63.4 dB, for channel 1/2, whereas the 2D-DPD resulted in the largest model error and DB-GMP resulted in model parameters that are three times more than those resulted with the proposed model with the same performance. As pre-distorter, the proposed model resulted in adjacent channel power ratio of -55.8/-54.6 dB for channel 1/2 and is 7-10 dB lower than those resulted with the 2D-DPD model and 2-4 dB lower compared with the DB-GMP model.

Place, publisher, year, edition, pages
Cambridge University Press, 2017
Keywords
Power Amplifiers, RF Front-ends, Behavioral modeling and digital predistortion of multi-band amplifiers
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-221397 (URN)10.1017/S1759078717000277 (DOI)000418998100010 ()2-s2.0-85018373558 (Scopus ID)
Note

QC 20180117

Available from: 2018-01-17 Created: 2018-01-17 Last updated: 2018-01-17Bibliographically approved
Khan, Z. A., Händel, P. & Isaksson, M. (2017). A Comparative Analysis of the Complexity/Accuracy Tradeoff in the Mitigation of RF MIMO Transmitter Impairments. In: 89th ARFTG Microwave Measurement Conference: Advanced Technologies for Communications, ARFTG 2017: . Paper presented at 89th ARFTG Microwave Measurement Conference, ARFTG 2017; Ala Moana Hotel, Honolulu; United States; 9 June 2017 through. Institute of Electrical and Electronics Engineers (IEEE), Article ID 8000827.
Open this publication in new window or tab >>A Comparative Analysis of the Complexity/Accuracy Tradeoff in the Mitigation of RF MIMO Transmitter Impairments
2017 (English)In: 89th ARFTG Microwave Measurement Conference: Advanced Technologies for Communications, ARFTG 2017, Institute of Electrical and Electronics Engineers (IEEE), 2017, article id 8000827Conference paper, Published paper (Refereed)
Abstract [en]

This paper presents a comparative analysis of the complexity accuracy tradeoff in state-of-the-art RF MIMO transmitter mitigation models. The complexity and accuracy of the candidate models depends on the basis functions considered in these models. Therefore, a brief description of the mitigation models is presented accompanied by derivations of the model complexities in terms of the number of FLOPs. Consequently, the complexity accuracy tradeoff in the candidate models is evaluated for a 2 × 2 RF MIMO transmitter. Furthermore, the model complexities are analyzed for increasing nonlinear orders and number of antennas.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2017
National Category
Signal Processing
Identifiers
urn:nbn:se:kth:diva-210023 (URN)10.1109/ARFTG.2017.8000827 (DOI)2-s2.0-85030244336 (Scopus ID)9781538627471 (ISBN)
Conference
89th ARFTG Microwave Measurement Conference, ARFTG 2017; Ala Moana Hotel, Honolulu; United States; 9 June 2017 through
Note

QC 20170628

Available from: 2017-06-27 Created: 2017-06-27 Last updated: 2017-11-30Bibliographically approved
Wahlström, J., Skog, I., Händel, P., Khosrow-Khavar, F., Tavakolian, K., Stein, P. K. & Nehorai, A. (2017). A Hidden Markov Model for Seismocardiography. IEEE Transactions on Biomedical Engineering, 64(10), 2361-2372
Open this publication in new window or tab >>A Hidden Markov Model for Seismocardiography
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2017 (English)In: IEEE Transactions on Biomedical Engineering, ISSN 0018-9294, E-ISSN 1558-2531, Vol. 64, no 10, p. 2361-2372Article in journal (Refereed) Published
Abstract [en]

We propose a hidden Markov model approach for processing seismocardiograms. The seismocardiogram morphology is learned using the expectation-maximization algorithm, and the state of the heart at a given time instant is estimated by the Viterbi algorithm. From the obtained Viterbi sequence, it is then straightforward to estimate instantaneous heart rate, heart rate variability measures, and cardiac time intervals (the latter requiring a small number of manual annotations). As is shown in the conducted experimental study, the presented algorithm outperforms the state-of-the-art in seismocardiogram-based heart rate and heart rate variability estimation. Moreover, the isovolumic contraction time and the left ventricular ejection time are estimated with mean absolute errors of about 5 [ms] and 9 [ms], respectively. The proposed algorithm can be applied to any set of inertial sensors; does not require access to any additional sensor modalities; does not make any assumptions on the seismocardiogram morphology; and explicitly models sensor noise and beat-to-beat variations (both in amplitude and temporal scaling) in the seismocardiogram morphology. As such, it is well suited for low-cost implementations using off-the-shelf inertial sensors and targeting, e.g., at-home medical services.

Place, publisher, year, edition, pages
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2017
Keywords
Cardiac time intervals, heart rate variability (HRV), hidden Markov model (HMM), seismocardiogram (SCG)
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-215801 (URN)10.1109/TBME.2017.2648741 (DOI)000411585100006 ()28092512 (PubMedID)2-s2.0-85026447100 (Scopus ID)
Note

QC 20171018

Available from: 2017-10-18 Created: 2017-10-18 Last updated: 2017-10-18Bibliographically approved
Pasku, V., De Angelis, A., Moschitta, A., Carbone, P., Nilsson, J.-O., Dwivedi, S. & Händel, P. (2017). A Magnetic Ranging-Aided Dead-Reckoning Positioning System for Pedestrian Applications. Paper presented at IEEE International Instrumentation and Measurement Technology Conference (I2MTC), MAY 23-26, 2016, Taipei, TAIWAN. IEEE Transactions on Instrumentation and Measurement, 66(5), 953-963
Open this publication in new window or tab >>A Magnetic Ranging-Aided Dead-Reckoning Positioning System for Pedestrian Applications
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2017 (English)In: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, no 5, p. 953-963Article in journal (Refereed) Published
Abstract [en]

This paper investigates the applicability of a developed Magnetic Positioning System (MPS) as a support for a dead-reckoning inertial navigation system (DR-INS) for pedestrian applications. The integrated system combines the complementary properties of the separate systems, operating over long periods of time and in cluttered indoor areas with partial nonline-of-sight conditions. The obtained results show that the proposed approach can effectively improve the coverage area of the MPS and the operation time with bounded errors of the DR-INS. In particular, a solution that provides bounded position errors of 1-2 m over significantly long periods of time up to 45 min, in realistic indoor environments, is demonstrated. Moreover, system applicability is also shown in those scenarios where arbitrary orientations of the MPS mobile node are considered and an MPS position estimate is not available due to less than three distance measurements.

Place, publisher, year, edition, pages
IEEE, 2017
Keywords
Dead reckoning (DR), indoor positioning, inertial navigation, magnetic fields, range measurement, resonators
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-208236 (URN)10.1109/TIM.2017.2649918 (DOI)000399246000012 ()2-s2.0-85011295568 (Scopus ID)
Conference
IEEE International Instrumentation and Measurement Technology Conference (I2MTC), MAY 23-26, 2016, Taipei, TAIWAN
Funder
VINNOVA
Note

QC 20170628

Available from: 2017-06-28 Created: 2017-06-28 Last updated: 2017-06-28Bibliographically approved
Alizadeh Khameneh, M. A., Rönnow, D., Händel, P. & Isaksson, M. (2017). A new Block-Structure Modeling Technique for RF Power Amplifiers in a 2x2 MIMO System. In: Milovanovic, BD Doncov, NS Stankovic, ZZ Dimitrijevic, TZ (Ed.), 2017 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications, TELSIKS 2017 - Proceeding: . Paper presented at 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS) Nis, Serbia; OCT 18-20, 2017 (pp. 224-227). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>A new Block-Structure Modeling Technique for RF Power Amplifiers in a 2x2 MIMO System
2017 (English)In: 2017 13th International Conference on Advanced Technologies, Systems and Services in Telecommunications, TELSIKS 2017 - Proceeding / [ed] Milovanovic, BD Doncov, NS Stankovic, ZZ Dimitrijevic, TZ, Institute of Electrical and Electronics Engineers (IEEE), 2017, p. 224-227Conference paper, Published paper (Refereed)
Abstract [en]

A new block-structure behavioral model is proposed for radio frequency power amplifiers in a 2x2 multiple-input multiple-output system including input cross-talk. The proposed model forms kernels of blocks of different nonlinear order that correspond to the significant frequency response of measured frequency domain Volterra kernels. The model can therefore well describe the input-output relationships of the nonlinear dynamic behavior of PAs. The proposed model outperforms conventional models in terms of model errors.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2017
Keywords
Nonlinear dynamic RF power amplifier, Volterra kernels, MIMO system, block-structural model
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-224099 (URN)10.1109/TELSKS.2017.8246268 (DOI)000425463200046 ()2-s2.0-85045971319 (Scopus ID)9781538618004 (ISBN)
Conference
13th International Conference on Advanced Technologies, Systems and Services in Telecommunications (TELSIKS) Nis, Serbia; OCT 18-20, 2017
Note

QC 20180314

Available from: 2018-03-14 Created: 2018-03-14 Last updated: 2018-06-04Bibliographically approved
Skog, I., Karagiannis, I., Bergsten, A. B., Harden, J., Gustafsson, L. & Händel, P. (2017). A Smart Sensor Node for the Internet-of-Elevators-Non-Invasive Condition and Fault Monitoring. IEEE Sensors Journal, 17(16), 5198-5208
Open this publication in new window or tab >>A Smart Sensor Node for the Internet-of-Elevators-Non-Invasive Condition and Fault Monitoring
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2017 (English)In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 17, no 16, p. 5198-5208Article in journal (Refereed) Published
Abstract [en]

The signal processing scheme of a smart sensor node for the Internet-of-Elevators is presented. The sensor node is a self-contained black box unit only requiring power to be supplied, which enables a cost efficient way to modernize existing elevator systems in terms of condition monitoring capabilities. The sensor node monitors the position of the elevator using an inertial navigation system in conjugation with a simultaneous localization and mapping framework. Features reflecting the elevator system's operation and health condition are calculated by evaluating the ride quality parameters defined by the ISO 18738-1 standards, the vibration versus frequency spectrum, and the vibration versus position spectrum. Abnormal stops are identified by detecting decelerations that deviate from the typical deceleration pattern of the elevator or when the stopping position of the elevator does not match the learned floor levels. Furthermore, the condition of the door system is monitored by tracking the magnetic field variations that the motion of the doors creates; the number of door openings and the time required for the doors to close are estimated. The capability and performance of the blacksignal processing scheme are illustrated through a series of experiments. The experiments show, inter alia, that using low-cost sensors similar to those in a smartphone, the position of the elevator car can, with 99.9% probability, be estimated with an error of less than 1 m for travels up to 43 s long. The experiments also indicate that small degradations in the doors' closing time can be detected from the magnetic field measurements.

Place, publisher, year, edition, pages
IEEE, 2017
Keywords
Predictive maintenance, intelligent sensors, accelerometers, magnetometers
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:kth:diva-212073 (URN)10.1109/JSEN.2017.2719630 (DOI)000406310500022 ()
Note

QC 20170816

Available from: 2017-08-16 Created: 2017-08-16 Last updated: 2017-08-16Bibliographically approved
Larsson, R., Skog, I. & Händel, P. (2017). Inertial Sensor Driven Smartphone and Automobile Coordinate System Alignment. In: 2017 IEEE 20TH INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS (ITSC): . Paper presented at 20th IEEE International Conference on Intelligent Transportation Systems (ITSC), OCT 16-19, 2017, Yokohama, JAPAN. IEEE
Open this publication in new window or tab >>Inertial Sensor Driven Smartphone and Automobile Coordinate System Alignment
2017 (English)In: 2017 IEEE 20TH INTERNATIONAL CONFERENCE ON INTELLIGENT TRANSPORTATION SYSTEMS (ITSC), IEEE , 2017Conference paper, Published paper (Refereed)
Abstract [en]

In this study a method is presented for estimating the orientation of an inertial measurement unit (IMU) located within an automobile, using only the measurements from the IMU itself. The orientation estimation problem is posed as a non-linear filtering probletn, which is solved using a marginalized particle filter. The performance of the proposed method is evaluated using a large collection of real-world data, collected by multiple drivers. The drivers used their own smartphones and had no restrictions on smartphone handling during drives. The orientation accuracy achieved with the proposed method is in the order of a few degrees; 50% of cases were below 5 degrees and 90% of cases were below 20 degrees.

Place, publisher, year, edition, pages
IEEE, 2017
Series
IEEE International Conference on Intelligent Transportation Systems-ITSC, ISSN 2153-0009
Keywords
IMU alipunent, Smartphone sensors, Smart-phone telematics
National Category
Civil Engineering
Identifiers
urn:nbn:se:kth:diva-230877 (URN)10.1109/ITSC.2017.8317592 (DOI)000432373000011 ()2-s2.0-85046288064 (Scopus ID)978-1-5386-1526-3 (ISBN)
Conference
20th IEEE International Conference on Intelligent Transportation Systems (ITSC), OCT 16-19, 2017, Yokohama, JAPAN
Note

QC 20180618

Available from: 2018-06-18 Created: 2018-06-18 Last updated: 2018-06-18Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2718-0262

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