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Händel, P. & Rönnow, D. (2020). MIMO and Massive MIMO Transmitter Crosstalk. IEEE Transactions on Wireless Communications, 19(3), 1882-1893
Open this publication in new window or tab >>MIMO and Massive MIMO Transmitter Crosstalk
2020 (English)In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 19, no 3, p. 1882-1893Article in journal (Refereed) Published
Abstract [en]

The effects of hardware-induced crosstalk in MIMO transmitters, subject to nonlinear power amplifier distortion, are considered in this paper. A methodology that provides tractable results and a clear understanding of the effects of crosstalk on transmitter performance is introduced and applied to different transmitter models. In particular, a physically motivated 2×2 MIMO transmitter model, which is subjected to input and output crosstalk, is studied in detail, as well as a behavior motivated transmitter model, which is subjected to linear crosstalk. For the latter structure, asymptotic results, when the number of transmitters tends to infinity, are derived. These results provide insight into different 1D and 2D transmitter structures in the massive MIMO scenario. The methodology provides tractable analytical results of the performance of the transmitter. It is shown that the transmitter crosstalk degrades the performance in terms of normalized mean squared error with 3 dB going from a 2×2 set-up to a 1D array of a massive amount of transmitters, and an additional 3 dB loss going from a 1D to 2D transmitter structure. Transmitter input power back-off optimization is further studied, with back-off determination that takes the effects of MIMO crosstalk into account in order to increase the energy efficiency of the transmitter.

Place, publisher, year, edition, pages
IEEE, 2020
Keywords
Orthogonal frequency division multiplexing (OFDM), input back-off, massive MIMO, power amplifier, transmitter hardware imperfections
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hig:diva-31379 (URN)10.1109/TWC.2019.2959534 (DOI)2-s2.0-85081726843 (Scopus ID)
Available from: 2020-01-07 Created: 2020-01-07 Last updated: 2020-03-30Bibliographically approved
Kumar, R., Tripathy, M. R. & Rönnow, D. (2020). Multi-resonant Bowtie Antenna with Modified Symmetric SRR for Wireless Applications. IETE Journal of Research , 66(1), 77-84
Open this publication in new window or tab >>Multi-resonant Bowtie Antenna with Modified Symmetric SRR for Wireless Applications
2020 (English)In: IETE Journal of Research , E-ISSN 0974-780X, Vol. 66, no 1, p. 77-84Article in journal (Refereed) Published
Abstract [en]

A modified symmetric split ring resonator (MSSRR) loaded bowtie antenna with multi-band features over a range of 1.6–7.1 GHz is proposed in this paper. The antenna is designed on FR4 substrate with relative permittivity εr = 4.1 and thickness 1.5 mm. The fabricated antenna size is 40 mm × 58 mm. The Modified Symmetric SRR used beneath the substrate is novel and consists of two circles that are broken into four quarter circles by four rods. The effect of MSSRR location and its geometry is investigated and analysed thoroughly. The measurement results of the fabricated antenna are in good agreement with the simulation results, which confirms the proposed antenna design’s properties. ANSYS High Frequency Structural Simulator (HFSS) software is used for simulating the antenna.

Place, publisher, year, edition, pages
Taylor & Francis Group, 2020
Keywords
Antenna, Bowtie, HFSS, Meta-material, Radiation pattern, SRR, Antennas, Computer software, Geometry, Microwave antennas, Ring gages, Wireless telecommunication systems, Bow tie, Bow-tie antennas, High frequency HF, Quarter circles, Relative permittivity, Split ring resonator, Wireless application, Directional patterns (antenna)
National Category
Signal Processing
Identifiers
urn:nbn:se:hig:diva-27359 (URN)10.1080/03772063.2018.1479663 (DOI)000512679800009 ()2-s2.0-85048508061 (Scopus ID)
Available from: 2018-06-25 Created: 2018-06-25 Last updated: 2020-03-02Bibliographically approved
Tripathy, M. R., Choudhary, V., Gupta, A., Ranjan, P. & Rönnow, D. (2019). A diamond-shaped fractal bow-tie antenna for THz applications. In: Sarma H., Borah S., Dutta N. (Ed.), Advances in Communication, Cloud, and Big Data: (pp. 97-104). Springer
Open this publication in new window or tab >>A diamond-shaped fractal bow-tie antenna for THz applications
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2019 (English)In: Advances in Communication, Cloud, and Big Data / [ed] Sarma H., Borah S., Dutta N., Springer , 2019, p. 97-104Chapter in book (Refereed)
Abstract [en]

A compact multiband diamond-shaped fractal bow-tie terahertz antenna is designed on FR4_epoxy substrate with permittivity 4.4. The dimension of substrate is 4 × 6 × 1.5 mm 3 . Multi-bands are obtained in S 11 versus frequency plots. The effects of creating defects in the ground plane of the antenna were studied and analyzed to get the optimized performance of antenna in the frequency bands at 0.500, 0.560, and 0.594 THz, respectively. © Springer Nature Singapore Pte Ltd. 2019.

Place, publisher, year, edition, pages
Springer, 2019
Keywords
Bow-tie, Ground defect surface, Multiband, THz antenna
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hig:diva-31103 (URN)10.1007/978-981-10-8911-4_11 (DOI)2-s2.0-85063206831 (Scopus ID)978-981-10-8910-7 (ISBN)978-981-10-8911-4 (ISBN)
Note

Export Date: 27 November 2019; Book Chapter; Correspondence Address: Tripathy, M.R.; Department of Electronics and Communication Engineering, ASET, Amity University Uttar PradeshIndia; email: mrtripathy@amity.edu

Available from: 2019-11-27 Created: 2019-11-27 Last updated: 2019-11-27Bibliographically approved
Choudhary, V., Rönnow, D. & Jansson, M. (2019). A Singular Value Decomposition Based Approach for Classifying Concealed Objects in Short Range Polarimetric Radar Imaging. In: 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring): . Paper presented at 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) (pp. 4109-4115). , Article ID 9017334.
Open this publication in new window or tab >>A Singular Value Decomposition Based Approach for Classifying Concealed Objects in Short Range Polarimetric Radar Imaging
2019 (English)In: 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring), 2019, p. 4109-4115, article id 9017334Conference paper, Published paper (Refereed)
Abstract [en]

In current research one of the main challenges in short range synthetic aperture radar (SAR) is electrically small structures and objects, which tend to unclear reinforced or through the wall objects, object orientation angle, and obscure contribution to extract the position of concealed multiple small objects. In this paper, ultra-wide-band (UWB) polarimetric radar was used to study reinforced objects and for estimation of object angle at short range. Electrically small 1D periodic mesh, 2D periodic meshes and differently oriented small objects or meshes could not be distinguished in conventional SAR images. A radar system with transmit and receive antennae mounted on a two dimensional scanning grid was used. The aim is non-destructive testing of built structures, in concrete slab manufacturing and for use in the renovation process. UWB short range radar data and images corresponding to different polarization states were analysed by using singular value decomposition (SVD). To perform decomposition, the proposed approach applies SVD to image data matrices produced from the back projection algorithm (BPA) to classify the different objects and identify the object angle. Then, sets of singular-components of different polarization states are analysed to classify objects. Also, the BPA algorithm is performed to construct the object images from the polarimetric radar signals. The object reflection varied with the polarimetric state of the UWB radar, which contributes to different object signatures (i.e., object intensity) since the object signature depends on the orientation, the size, and the number of objects. Object orientation with respect to the radar system and object anisotropy could be determined from the ratio of the different polarimetric singular-components. This proposed complex data analysis method demonstrates the usefulness of the SVD using BPA in extracting more information about and for classifying an object.

Keywords
Radar imaging, Antenna measurements, Radar antennas, Ultra wideband radar, Radar polarimetry, Springs
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hig:diva-32007 (URN)10.1109/PIERS-Spring46901.2019.9017334 (DOI)2-s2.0-85081990211 (Scopus ID)978-1-7281-3403-1 (ISBN)
Conference
2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring)
Note

This work was supported by the European Commission within the European Regional Development Fund, through the Swedish Agency for Economic and Regional Growth, and in part by Region-Gävleborg.

Available from: 2020-03-06 Created: 2020-03-06 Last updated: 2020-03-30Bibliographically approved
Sarika, n., Kumar, R., Tripathy, M. T. & Rönnow, D. (2019). An approach to improve gain and bandwidth in bowtie antenna using frequency selective surface. In: Bijaya Ketan Panigrahi, Munesh C. Trivedi, Krishn K. Mishra, Shailesh Tiwari, Pradeep Kumar Singh (Ed.), Smart Innovations in Communication and Computational Sciences: Proceedings of ICSICCS 2017, Volume 1. Paper presented at International Conference on Smart Innovations in Communications and Computational Sciences (ICSICCS 2017), Punjab, India, 23-24 June 2017 (pp. 219-227). Springer
Open this publication in new window or tab >>An approach to improve gain and bandwidth in bowtie antenna using frequency selective surface
2019 (English)In: Smart Innovations in Communication and Computational Sciences: Proceedings of ICSICCS 2017, Volume 1 / [ed] Bijaya Ketan Panigrahi, Munesh C. Trivedi, Krishn K. Mishra, Shailesh Tiwari, Pradeep Kumar Singh, Springer, 2019, p. 219-227Conference paper, Published paper (Refereed)
Abstract [en]

A novel approach of improving gain and bandwidth of bowtie antenna using Frequency Selective Surface (FSS) is presented. A 42 × 66 mm2 bowtie antenna is used. The 5 mm × 5 mm FSS unit cell consists of metallic square loop and grid wires on FR4 substrate with permittivity of 4.4 and loss tangent = 0.02. The effect of FSS layer on bowtie antenna is investigated in terms of parameters like gain and bandwidth. Simulation results show that gain and bandwidth of the bowtie antenna gets increased by a factor of two when the FSS layer is kept on it. Further, the effect of change of height of the substrate on gain and bandwidth is also studied. The proposed structure shows applications in X-band and Ku-band range. High-Frequency Structural Simulator (HFSS) software is used for the simulation. © Springer Nature Singapore Pte Ltd. 2019.

Place, publisher, year, edition, pages
Springer, 2019
Series
Advances in Intelligent Systems and Computing, ISSN 2194-5357, E-ISSN 2194-5365 ; 669
Keywords
Bandwidth enhancement, Bowtie, Frequency selective surface, HFSS, Bandwidth, Computer software, Microwave antennas, Bow tie, Bow-tie antennas, Change of heights, Frequency selective surface (FSS), Gain and bandwidths, High frequency HF, Frequency selective surfaces
National Category
Signal Processing
Identifiers
urn:nbn:se:hig:diva-27652 (URN)10.1007/978-981-10-8968-8_19 (DOI)2-s2.0-85049349640 (Scopus ID)978-981-10-8967-1 (ISBN)978-981-10-8968-8 (ISBN)
Conference
International Conference on Smart Innovations in Communications and Computational Sciences (ICSICCS 2017), Punjab, India, 23-24 June 2017
Available from: 2018-08-15 Created: 2018-08-15 Last updated: 2019-11-29Bibliographically approved
Alizadeh, M., Händel, P. & Rönnow, D. (2019). Behavioral modeling and digital pre-distortion techniques for RF PAs in a 3 × 3 MIMO system. International journal of microwave and wireless technologies, 11(10), 989-999
Open this publication in new window or tab >>Behavioral modeling and digital pre-distortion techniques for RF PAs in a 3 × 3 MIMO system
2019 (English)In: International journal of microwave and wireless technologies, ISSN 1759-0795, E-ISSN 1759-0787, Vol. 11, no 10, p. 989-999Article in journal (Refereed) Published
Abstract [en]

Modern telecommunications are moving towards (massive) multi-input multi-output systems in 5th generation (5G) technology, increasing the dimensionality of the system dramatically. In this paper, the impairments of radio frequency (RF)power amplifiers (PAs) in a 3x3 MIMO system are compensated in both time and frequency domains. A three-dimensional(3D) time-domain memory polynomial-type model is proposed as an extension of conventional 2D models. Furthermore, a 3D frequency-domain technique is formulated based on the proposed time-domain model to reduce the dimensionality of the model, while preserving the performance in terms of model errors. In the 3D frequency-domain technique, the bandwidth of a system is split into several narrow sub-bands, and the parameters of the system are estimated for each subband. This approach requires less computational complexity, and also the procedure of the parameters estimation for each sub-band can be implemented independently. The device-under-test (DUT) consists of three RF PAs including input and output cross-talk channels. The proposed techniques are evaluated in both behavioural modelling and digital pre-distortion(DPD) perspectives. The results show that the proposed DPD technique can compensate the errors of non-linearity and memory effects by about 23.5 dB and 7 dB in terms of the normalized mean square error and adjacent channel leakage ratio, respectively.

Place, publisher, year, edition, pages
Cambridge University Press, 2019
Keywords
Radio frequency power amplifier, non-linearity, memory effects, multiple-input multiple-output (MIMO), digital pre-distortion.
National Category
Signal Processing
Identifiers
urn:nbn:se:hig:diva-29304 (URN)10.1017/S1759078719000862 (DOI)000500870900001 ()2-s2.0-85067662944 (Scopus ID)
Available from: 2019-01-11 Created: 2019-02-18 Last updated: 2020-03-25Bibliographically approved
Ivanchenko, I., Khruslov, M., Popenko, N. & Rönnow, D. (2019). Combined L–S-bands antenna module. IET Microwaves, Antennas & Propagation, 13(5), 541-545
Open this publication in new window or tab >>Combined L–S-bands antenna module
2019 (English)In: IET Microwaves, Antennas & Propagation, ISSN 1751-8725, E-ISSN 1751-8733, Vol. 13, no 5, p. 541-545Article in journal (Refereed) Published
Abstract [en]

A combined L-S-band antenna module consists of four rectangular patch antennas, two of which operate at the frequencies of the first harmonics (L-band), and two others at the frequencies of the second harmonics (S-band). The module is intended for use in super heterodyne signal reception circuits, for example in studying the various non-linear phenomena. The results of this study are presented in terms of improving the performance of each antenna and minimising their mutual influence. The resonance frequencies of the L-band antenna differ by 50MHz. All the antennas radiate close to the zenith and their beamwidths in two principal planes are virtually the same. At the resonance frequencies, the reflection coefficient is S-11<-30dB for the transmitting antenna, and S-11<-20dB for the receiving antenna. The minimum allowable distance between the antennas is determined, at which their mutual influence can be neglected (S-12<-50dB).

Place, publisher, year, edition, pages
IET, 2019
Keywords
heterodyne detection, transmitting antennas, antenna radiation patterns, microstrip antennas, receiving antennas, L-band antenna, resonance frequencies, transmitting antenna, receiving antenna, L-S-bands antenna module, rectangular patch antennas, super heterodyne signal reception circuits, frequency 50, 0 MHz
National Category
Signal Processing
Identifiers
urn:nbn:se:hig:diva-30500 (URN)10.1049/iet-map.2018.5130 (DOI)000465255900002 ()2-s2.0-85064208155 (Scopus ID)
Available from: 2019-08-15 Created: 2019-08-15 Last updated: 2019-11-26Bibliographically approved
Händel, P. & Rönnow, D. (2019). Modeling Mixer and Power Amplifier Impairments. IEEE Microwave and Wireless Components Letters, 29(7), 441-443, Article ID 8733818.
Open this publication in new window or tab >>Modeling Mixer and Power Amplifier Impairments
2019 (English)In: IEEE Microwave and Wireless Components Letters, ISSN 1531-1309, E-ISSN 1558-1764, Vol. 29, no 7, p. 441-443, article id 8733818Article in journal (Refereed) Published
Abstract [en]

Combating the effects of mixer and power amplifier (PA) imperfections on transmitter performance is crucial for the design of wireless systems. PA compression and in-phase/quadrature imbalance are analyzed for a single-input-single-output transmitter model. The influence of the imperfection on the normalized mean squared error (NMSE) of the transmitter is studied using an analytical framework that relies on the classic Bussgang theory. The study concludes with a closed-form expression for the NMSE that provides insights into the behavior of the transmitter. © 2019 IEEE.

Place, publisher, year, edition, pages
IEEE, 2019
Keywords
Dirty radio, input backoff, orthogonal frequency division multiplexing (OFDM), power amplifier (PA), Mean square error, Mixers (machinery), Orthogonal frequency division multiplexing, Radio frequency amplifiers, Transmitters, Closed-form expression, In-phase/quadrature, Normalized mean squared errors, Single input single output, Transmitter model, Wireless systems, Power amplifiers
National Category
Signal Processing
Identifiers
urn:nbn:se:hig:diva-30545 (URN)10.1109/LMWC.2019.2915647 (DOI)000474589400001 ()2-s2.0-85068688857 (Scopus ID)
Funder
Swedish Agency for Economic and Regional Growth
Note

Funding: The work of D. Ronnow was supported in part by the European Commission within the European Regional Development Fund through the Swedish Agency for Economic and Regional Growth and in part by Region Gavleborg.

Available from: 2019-08-22 Created: 2019-08-22 Last updated: 2019-08-26Bibliographically approved
Rönnow, D. & Händel, P. (2019). Nonlinear distortion noise and linear attenuation in MIMO systems - theory and application to multiband transmitters. IEEE Transactions on Signal Processing, 67(20), 5203-5212, Article ID 8805179.
Open this publication in new window or tab >>Nonlinear distortion noise and linear attenuation in MIMO systems - theory and application to multiband transmitters
2019 (English)In: IEEE Transactions on Signal Processing, ISSN 1053-587X, E-ISSN 1941-0476, Vol. 67, no 20, p. 5203-5212, article id 8805179Article in journal (Refereed) Published
Abstract [en]

Nonlinear static multiple-input multiple-output (MIMO) systems are analyzed. The matrix formulation of Bussgang's theorem for complex Gaussian signals is rederived and put in the context of the multivariate cumulant series expansion. The attenuation matrix is a function of the input signals' covariance and the covariance of the input and output signals. The covariance of the distortion noise is in addition a function of the output signal's covariance. The effect of the observation bandwidth is discussed. Models of concurrent multiband transmitters are analyzed. For a transmitter with dual non-contiguous bands expressions for the normalized mean square error (NMSE) vs input signal power are derived for uncorrelated, partially correlated, and correlated input signals. A transmitter with arbitrary number of non-contiguous bands is analysed for correlated and uncorrelated signals. In an example, the NMSE is higher when the input signals are correlated than when they are uncorrelated for the same input signal power and it increases with the number of frequency bands. A concurrent dual band amplifier with contiguous bands is analyzed; in this case the NMSE depends on the bandwidth of the aggregated signal.

Place, publisher, year, edition, pages
IEEE, 2019
Keywords
Bussgang theory, carrier aggregation, concurrent dual band, MIMO, multiband transmitter, nonlinear distortion
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hig:diva-30580 (URN)10.1109/TSP.2019.2935896 (DOI)000485741500001 ()2-s2.0-85077734457 (Scopus ID)
Note

Funding: European Commission within the European Regional Development Fund;   Swedish Agency for Economic and Regional Growth; Region Gavleborg

Available from: 2019-08-26 Created: 2019-08-26 Last updated: 2020-01-20Bibliographically approved
Sarika, ., Tripathy, M. R. & Rönnow, D. (2018). A wideband frequency selective surface reflector for 4G/X-Band/Ku-Band. Progress In Electromagnetics Research C, 81, 151-159
Open this publication in new window or tab >>A wideband frequency selective surface reflector for 4G/X-Band/Ku-Band
2018 (English)In: Progress In Electromagnetics Research C, ISSN 1937-8718, E-ISSN 1937-8718, Vol. 81, p. 151-159Article in journal (Refereed) Published
Abstract [en]

A Frequency Selective Surface (FSS) reflector with wideband response for 4G/X-band/Ku-band is proposed. The wideband FSS reflector consists of cascaded dual-layer patch FSS which is etched on separate layers of FR4 substrate. The targeted frequency range is 5–16 GHz. A wide stopband of 10.4 GHz (100% percent bandwidth) is obtained with two layers in cascade. The Equivalent Circuit (EC) method is used to approximate the simulated results. An extensive parametric study is also carried out to understand the effect of various combinations of FSS layers and their disposition. A panel of final FSS is fabricated where measured and simulated results agree well.

Place, publisher, year, edition, pages
Electromagnetics Academy, 2018
Keywords
Equivalent circuits, Reflection, Dual layer, FR4 substrates, Frequency ranges, Frequency selective surface (FSS), Parametric study, Simulated results, Wide band frequencies, Wide stopband, Frequency selective surfaces
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:hig:diva-26241 (URN)2-s2.0-85042380788 (Scopus ID)
Available from: 2018-03-15 Created: 2018-03-15 Last updated: 2018-04-25Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-2887-049x

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