| 1. |
- Bolin, Thomas, et al.
(författare)
-
Two-antenna receive diversity performance in indoor environment
- 2005
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Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 1350-911X .- 0013-5194. ; 41:22, s. 1205-1206
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Tidskriftsartikel (refereegranskat)abstract
- Receive diversity gain performance of a two-antenna setup in an office environment is reported. The terminal is handheld in front of the user simulating a data mode scenario while walking around. The dual polarised base station sector antenna is placed at the end of a corridor. The results indicate that experimentally achieved diversity performance is similar to previously predicted theoretical data.
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| 2. |
- Plicanic, Vanja, et al.
(författare)
-
Actual diversity performance of a multiband diversity antenna with hand and head effects
- 2009
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Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X. ; 57:5, s. 1547-1556
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Tidskriftsartikel (refereegranskat)abstract
- Using the metric actual diversity gain (ADG), diversity performance is investigated for a compact mobile terminal prototype with two internal, triple frequency band antennas in four different cases of user interaction. ADG is presented as a preferred alternative to apparent diversity gain and effective diversity gain. Absorption due to user proximity causes degradation and imbalance in mean effective gain of the antennas over the frequency bands, contributing to a degradation in diversity performance. However, user-induced changes in the antenna patterns cause a decrease in correlation in the low frequency band, which facilitates increased diversity gain. The study reveals that a significant net diversity gain, i.e., ADG of 5-8 dB compared to a single antenna prototype, can be achieved using multiband antennas in the proximity of a user, even at low frequencies for antennas with high mutual coupling.
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| 3. |
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| 4. |
- Plicanic, Vanja, et al.
(författare)
-
Antenna diversity evaluation for mobile terminals
- 2006
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Ingår i: European Space Agency, (Special Publication) ESA SP. - 0379-6566 .- 1609-042X. ; 626 SP
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Konferensbidrag (refereegranskat)abstract
- In this paper we are focusing on the practical, engineering way of evaluating and characterizing the multi-channel antenna solutions on the mobile terminal. Two methods of calculating the parameters, describing the diversity performance, are described and the practical use of the methods in simulations and measurements are presented and evaluated. The time saving aspect of using the scattering parameters is lifted forward but also its limitations. For comparison, a statistical method for calculating Diversity Gain is also presented. This evaluation is performed for two multi-channel antenna solutions with different characteristics for the purpose of characterizing different diversity performances.
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| 5. |
- Plicanic, Vanja, et al.
(författare)
-
Capacity maximisation of a handheld MIMO terminal with adaptive matching in an indoor environment
- 2011
-
Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 1350-911X .- 0013-5194. ; 47:16, s. 900-901
-
Tidskriftsartikel (refereegranskat)abstract
- This letter reports the capacity performance of a handheld dual-band dual-antenna compact MIMO terminal, which utilizes uncoupled adaptive impedance matching for capacity maximisation. The capacity is evaluated at 0.825 GHz and 2.35 GHz in an indoor office environment. The results show that adaptive matching enhances capacity by up to 44% and 22% at the low and high frequency bands, respectively, relative to no matching. At the low band, the capacity gain is attributed to both increased received power and decreased channel eigenvalue dispersion, whereas at the high band, the capacity gain is only due to increased power.
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| 6. |
- Plicanic, Vanja, et al.
(författare)
-
Channel capacity performance of multi-band dual antenna in proximity of a user
- 2009
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Ingår i: 2009 IEEE International Workshop on Antenna Technology: Small Antennas and Novel Metamaterials (IWAT). - 9781424443956 ; , s. 41402-41402
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Konferensbidrag (refereegranskat)abstract
- This paper presents an evaluation of single input single output (SISO), single input multiple output (SIMO) and multiple input multiple output (MIMO) channel capacities for a dual antenna prototype in proximity of a user. The dual antenna prototype mimics today’s small mobile phone design in size and in comprising internal, compact, multi-band antennas. Four different user cases are evaluated by measuring the antenna radiation performance for each of the different interactions between a phantom user and the antenna. Measurements of a single antenna prototype with user are also performed for comparisons between the SISO case and the SIMO/MIMO cases. Depending on the user interaction case, the MIMO capacity of the prototype is between 40-90% at 850 MHz and 60-80% at 2100 MHz higher than the SISO performance of the single antenna prototype or the best antenna on the dual antenna prototype.
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| 7. |
- Plicanic, Vanja
(författare)
-
Characterization and Enhancement of Antenna System Performance in Compact MIMO Terminals
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Co-band multiple-antenna implementation in compact user terminals is necessary for harvesting the full potential of diversity and multiple-input multiple-output (MIMO) technology in cellular communication systems. The recent worldwide deployment of Long Term Evolution (LTE), which requires the use of MIMO technology in the downlink, adds to the urgency of achieving both practical and optimal multiple-antenna systems in user terminals. Contrary to conventional understanding, an optimal multiple-antenna implementation does not only involve the design and placement of antenna elements in the terminals, but extends beyond the antenna elements and common antenna parameters to comprise interactions with the near field user and the propagation environment. Moreover, these interactions are non-static, which implies that the multiple-antenna system must adapt to the prevailing overall communication channel in order to assure the highest performance gains. This doctoral thesis aims to address several key issues in optimal multiple-antenna system design for compact multi-band MIMO terminals, with the first half (Papers I to III) focusing on the performance characterization of such terminals in the presence of user interaction and propagation channel, under the challenging constraint that the terminals are compact. The second half of the thesis (Papers IV to VI) considers two performance enhancement approaches suitable for compact MIMO terminals in realistic usage conditions. In particular, the potential benefits of harmonizing compact multiple-antenna systems with the propagation channel and user influence are determined with respect to reconfigurability in antenna patterns and impedance matching circuits. In Paper I, the diversity performance of internal multiple antennas with multi-band coverage in a mock-up with the size of a typical mobile handset is investigated in different user interaction scenarios. For comparison, a second mock-up with only one multi-band antenna is also evaluated in the same user cases. An ideal uniform propagation environment is assumed. The performance at frequency bands below and above 1 GHz are presented and analyzed in detail. Paper II extends the study in Paper I by evaluating the single-input multiple-output (SIMO) and MIMO capacity performance of the same antenna prototypes under the same user interaction scenarios and propagation environment. In Paper III, the impacts of gain imbalance and antenna separation on the throughput performance of a dual-dipole configuration are studied at frequencies below and above 1 GHz in a repeatable dynamic multi-path environment, using a live HSPA network. Since the compactness of a user terminal has implications on the antenna separation and gain imbalance of the multiple antennas, the focus is to gain knowledge on how these two factors affect the end user experience in practice. In Paper IV, three simple dual-antenna topologies implemented in compact smart phone prototypes of identical form factors are evaluated in MIMO channel measurements in noise-limited and interference-limited urban scenarios. Each dual-antenna topology is intentionally designed to provide a distinct set of antenna patterns. The goal is to investigate the potential of antenna system design as one of the key performance differentiators in real terminal implementations. Paper V extends the work in Paper IV by introducing user interaction to the same MIMO channel measurement setup. Furthermore, the focus of this paper is on the evaluation of both the average and local channel performances and their potential enhancements. Finally, Paper VI ascertains the potential capacity gains of applying uncoupled adaptive matching to a compact dual-antenna terminal in an indoor office environment, under a realistic user scenario. The performance gains are evaluated by means of extensive MIMO channel measurements at frequency bands below and above 1 GHz.
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| 8. |
- Plicanic, Vanja, et al.
(författare)
-
Diversity mechanisms and MIMO throughput performance of a compact six-port dielectric resonator antenna array
- 2010
-
Ingår i: 2010 International Workshop on Antenna Technology (iWAT). - 9781424448838
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Konferensbidrag (refereegranskat)abstract
- This paper demonstrates multiple-input-multiple-output (MIMO) throughput performance of a six-port dielectric resonator antenna (DRA) array for Wireless-LAN applications in a measured indoor office environment when a six-port dual-polarized patch array is used at the transmitter. The throughput was obtained using an IEEE802.11n/Draft 5.00 simulator for measured channels with different antenna and propagation setups. The throughput performance of the patch-DRA array set-up is found to be similar to that of a set-up with six-port monopole arrays at the receive and transmit ends in the non-line-of sight (NLOS) environment. The compact design of the DRA array causes lower port efficiencies relative to those of the monopole array, notwithstanding the compact DRA array is shown in this paper to effectively utilize angle, polarization and spatial diversity mechanisms to achieve comparable throughput performance.
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| 9. |
- Plicanic, Vanja, et al.
(författare)
-
Diversity mechanisms of a compact dielectric resonator antenna array for high MIMO throughput performance
- 2009
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The multiple-input-multiple-output (MIMO) throughput of a given wireless system is a better indication of end user experience, as compared to conventional MIMO performance metrics such as capacity and diversity gains. This paper demonstrates throughput performance of a six-port dielectric resonator antenna (DRA) array for Wireless-LAN (WLAN) applications in a measured indoor office environment when a six-port dual-polarized patch array is used at the transmit end. The throughput was obtained using an IEEE 802.11n/Draft 5 simulator for measured channels with different antenna and propagation setups. The throughput performance of the patch-DRA array set-up is found to be similar to that of a set-up with six-port monopole arrays at the transmit and receive ends in the non-line-of sight (NLOS) environment. Even though the compact design of the DRA array causes lower port efficiencies relative to those of the reference monopole array, the compact DRA array can effectively utilize angle, polarization and spatial diversity mechanisms to achieve comparable throughput performance.
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| 10. |
- Plicanic, Vanja, et al.
(författare)
-
Experimental evaluation of MIMO terminal antenna configurations in noise- and interference-limited urban scenarios
- 2011
-
Ingår i: Proceedings of the 5th European Conference on Antennas and Propagation (EUCAP). - 9788882020743
-
Konferensbidrag (refereegranskat)abstract
- In this paper, we compare capacity performances of three terminal dual-antenna configurations at 2.65 GHz based on extensive 2 by 2 multiple-input multiple-output (MIMO) channel measurements in an urban macrocellular environment. Both noise- and interference-limited scenarios are investigated. Our results show that, on average over the measurement route, the capacity performance is mainly determined by the received power. However, locally along the route, the eigenvalue dispersion of the channel can be the dominant factor that influences the capacity performance. In addition, significant differences in the local performances of the terminal antenna configurations along the route give an indication that antenna reconfigurability is a promising approach to maximize capacity.
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| 11. |
- Plicanic, Vanja, et al.
(författare)
-
Free space performance comparison of MIMO terminal antennas in noise- and interference-limited urban environments
- 2010
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This contribution comprises a comparison of capacity performances of MIMO terminal antenna configurations for smart phones at 2.65 GHz, measured in an extensive 2×2 MIMO measurement campaign in noise- and interference-limited urban environments. Whereas, on average along the route, the performances where dictated by the received power, locally the eigenvalue dispersion of the communication channel, and also interference channel, is shown to have significant impact on the capacity. Thus, locally, depending on the antenna-channel interaction, different cases of best performances are observed among the evaluated antenna terminals. The differences in the performance along the route indicate a potential of adaptivity for maximizing MIMO capacity.
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| 12. |
- Plicanic, Vanja, et al.
(författare)
-
Impact of spacing and gain imbalance between two dipoles on HSPA throughput performance
- 2009
-
Ingår i: Electronics Letters. - : Institution of Engineering and Technology (IET). - 1350-911X .- 0013-5194. ; 45:21, s. 1063-1064
-
Tidskriftsartikel (refereegranskat)abstract
- This Letter reports the throughput performance of two parallel half-wavelength dipoles with different antenna spacings and antenna gain imbalances for two frequency bands in a live High-Speed Packet Access (HSPA) network. It was found that an antenna spacing of 0.25 wavelengths and gain imbalances of up to 6 dB are sufficient to provide significant throughput gain for the same transmit power, or equivalently, an increase in network coverage for a given throughput, as compared to a single dipole.
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| 13. |
- Plicanic, Vanja, et al.
(författare)
-
Influence of user hand on the performance of a multiband diversity antenna
- 2008
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The increasing demand on improved reception and high data throughput brings into focus the design of compact multiband antenna terminals with diversity reception capability. In particular, the influence of user on diversity performance is of current interest. In this paper, the diversity performance of compact tri-band antennas (WCDMA850, WCDMA1800 and UMTS 2100) for mobile handsets is evaluated in the data mode position. The results indicate that the user hand has a significant negative effect on the mean effective gains of the diversity antennas. On the other hand, the signal correlation is relatively unaffected by the hand, and it even improved for the WCDMA850 band. However, the decrease in correlation between the branches in the WCDMA850 band is inadequate to offset the degradation in diversity system gain resulting from the reduced mean effective gains. Moreover, the loss of efficiency due to mutual coupling is particularly severe at the WCDMA850 band. Consequently, only a small diversity system gain of less than 1 dB is obtained for the lowest band, whereas a 5 dB gain is achieved for the higher bands.
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| 14. |
- Plicanic, Vanja, et al.
(författare)
-
On MIMO capacity of a dual multiband antenna prototype with user interactions
- 2008
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- This paper presents an evaluation of single input single output (SISO), single input multiple output (SIMO) and multiple input multiple output (MIMO) channel capacities for a dual antenna prototype in proximity of a user. The dual antenna prototype mimics today’s small mobile phone design in size and in comprising internal, compact, multi-band antennas. Four different user cases are evaluated by measuring the antenna radiation performance for each of the different interactions between a phantom user and the antenna. Measurements of a single antenna prototype with user are also performed for comparisons between the SISO case and the SIMO/MIMO cases. Depending on the user interaction case, the MIMO capacity of the prototype is between 40-90% at 850 MHz and 60-80% at 2100 MHz higher than the SISO performance of the single antenna prototype or the best antenna on the dual antenna prototype.
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| 15. |
- Plicanic, Vanja
(författare)
-
Performance characterization of compact multiple antenna terminals
- 2009
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Co-band multi-antenna implementation in realistic compact user terminals is of great interest to the wireless telecom industry for achieving high data rates. This licentiate thesis focuses on the mechanisms behind the implementation of multiple antennas for diversity and MIMO gains in everyday user terminals. Specifically, the effects of compactness, user interaction and propagation channel on the implementation are investigated through extensive simulation and measurement studies.
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| 16. |
- Plicanic, Vanja, et al.
(författare)
-
Performance of a multiband diversity antenna with hand effects
- 2008
-
Ingår i: International Workshop on Antenna Technology (iWAT 2008). ; , s. 478-481
-
Konferensbidrag (refereegranskat)abstract
- The implementation of multiband diversity antennas in compact mobile handsets, for the purpose of increasing transmission quality, is a topic of current interest in the mobile phone industry. In order to achieve the expected performance improvement in typical operating conditions, we not only have to contend with the challenges of designing multiple multiband antennas, which are closely spaced within the compact handset and thus strongly interacting with one another electromagnetically [1], we also need to keep in check the electromagnetic interaction between the whole antenna system (i.e., the handset) and the user. Previous studies have concluded that the presence of a user degrades the mean effective gain (MEG) of the diversity antennas significantly [1]-[3]. Different results have been presented on the effect of the user on the correlation coefficient, no effect [1] and a significant increase of the correlation [2], [3], have been pointed out. However, these studies have been performed on simple single band antennas in talk position. In this paper a more realistic approach is presented by choosing the diversity antenna system to comprise compact versions of PIFA and monopole antennas which cover three WCDMA bands: WCDMA850, WCDMA1800 and UMTS [4]. Such compact antennas are easily conformable for small mobile phone products [4]. The choice of the bands, as well as the evaluation of the diversity performance for the data mode position, is derived from the increasing demand on HSDPA applications in the mobile phone market. The investigation of user interaction presented in this paper focuses on the comparison between the free space and data mode diversity performance of a tri-band “stick” phone size prototype in the uniform 3D propagation environment. A state-of-the-art phantom hand from IndexSAR [5] is used to hold the diversity prototype in the data mode position.
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| 17. |
- Plicanic, Vanja, et al.
(författare)
-
Performance of handheld MIMO terminals in noise- and interference-limited urban macrocellular scenarios
- 2012
-
Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X. ; 60:8, s. 3901-3912
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract in UndeterminedMultiple-antenna handheld terminals are an integral part of the latest mobile communication systems, due to the adoption of multiple-input multiple-output (MIMO) technology. In this contribution, MIMO performances of three multiple-antenna configurations for smart phones are investigated in an urban macrocellular environment, based on an extensive MIMO measurement campaign at 2.65 GHz. The smart phones were held in a two-hand user grip position and both downlink noise- and interference-limited scenarios were evaluated. Our results show that, overall along the test route, the capacity performances are dictated by the power of the communication links. Nevertheless, locally, the multipath richness of the communication channel can have a significant impact on the capacity performances. In addition to the terminal antenna configurations, spatial and cross polarization references were also utilized to further illustrate the importance of multipath richness in both the desired and the interference channels. Moreover, the differences in the local capacity performances along the route for the three antenna configurations give a first indication of the potential benefit in implementing reconfigurable multiple antennas. If switching for maximum capacity is applied between the terminal antenna configurations in the two-hand grip position, average capacity improvements of up to 17% and 30% for local 20 m route sections are observed in the noise- and the interference-limited scenarios, respectively.
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| 18. |
- Tian, Ruiyuan, et al.
(författare)
-
A compact six-port dielectric resonator antenna array: MIMO channel measurements and performance analysis
- 2010
-
Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X. ; 58:4, s. 1369-1379
-
Tidskriftsartikel (refereegranskat)abstract
- MIMO systems ideally achieve linear capacity gain proportional to the number of antennas. However, the compactness of terminal devices limits the number of spatial degrees of freedom (DOFs) in such systems, which motivates efficientantenna design techniques to exploit all available DOFs. In this contribution, we present a compact six-port dielectric resonator antenna (DRA) array which utilizes spatial, polarization and angle diversities. To evaluate the proposed DRA array, a measurement campaign was conducted at 2.65GHz in indoor officescenarios for four 6 × 6 multiple antenna systems. Compared to the reference system of monopole arrays which only exploit spatial diversity, the use of dual-polarized patch antennas at the transmitter enriches the channel’s DOF in the non-line-of-sight scenario. Replacing the monopole array at the receiver withthe DRA array that has a 95% smaller ground plane, the 10% outage capacity evaluated at 10 dB reference signal-to-noise ratio becomes equivalent to that of the reference system, due to the DRA’s rich diversity characteristics. In the line-of-sight scenario, the DRA array gives a higher DOF than the monopole array asthe receive counterpart to the transmit patch array. However, the outage capacity is 1.5 bits/s/Hz lower, due to the DRA array’s lower channel gain.
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| 19. |
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| 20. |
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| 21. |
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| 22. |
- Vasilev, Ivaylo, et al.
(författare)
-
Experimental investigation of adaptive impedance matching for a MIMO terminal with CMOS SOI tuners
- 2016
-
Ingår i: IEEE Transactions on Microwave Theory and Techniques. - 0018-9480. ; 64:5, s. 1622-1633
-
Tidskriftsartikel (refereegranskat)abstract
- It is well known that user proximity introduces absorption and impedance mismatch losses that severely degrade multiple-input multiple-output (MIMO) performance of handset antennas. In this work, we experimentally verified the potential of adaptive impedance matching (AIM) to mitigate user interaction effects and identified the main AIM gain mechanism in realistic systems. A practical setup including custom-designed CMOS silicon-on-insulator (SOI) impedance tuners implemented on a MIMO handset was measured in three propagation environments and 10 real user scenarios. The results indicate that AIM can improve MIMO capacity by up to 42% equivalent to 3.5 dB of multiplexing efficiency (ME) gain. Taking into account the measured losses of 1 dB in the integrated tuners, the maximum net ME gain is 2.5 dB suggesting applicability in practical systems. Variations in ME gains of up to 1.5 dB for different hand-grip styles were mainly due to differences in impedance mismatch and tuner loss distribution. The study also confirmed earlier results on the significant differences in mismatch and absorption between phantoms and real users, in which the phantoms underestimated user effects and therefore AIM gains. Finally, propagation environments of different angular spreads were found to give only minor ME gain variations.
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| 23. |
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| 24. |
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| 25. |
- Vasilev, Ivaylo, et al.
(författare)
-
Impact of antenna design on MIMO performance for compact terminals with adaptive impedance matching
- 2016
-
Ingår i: IEEE Transactions on Antennas and Propagation. - 0018-926X. ; 64:4, s. 1454-1465
-
Tidskriftsartikel (refereegranskat)abstract
- Using the metrics of channel capacity and multiplexing efficiency, the adaptive impedance matching (AIM) performances of two multiple-input multiple-output (MIMO) terminals with different antenna designs were evaluated and compared. The evaluation was performed in LTE Band 18 Downlink (860-875 MHz) under realistic usage conditions of two measured user handgrips and simulated propagation channels with different angular spreads (ASs). The results provide potential performance gains from AIM based on realistic MIMO terminal prototypes, and the underlying mechanisms by which the gains were achieved, which can serve as antenna and AIM circuit design guidelines. In particular, the evaluation revealed that ideal uncoupled AIM networks can increase the capacity by up to 52% relative to 50 ohm terminations. However, the observed gains depend heavily on the antenna design, the user scenario and the channel’s angular spread. For example, the wideband design in different user cases experienced capacity gain of 4-9% from AIM in uniform 3D channels, in contrast to the 1.3-44% gain seen in a conventional narrowband design. In non-uniform channels with small ASs, the AIM gain for different mean incident angles depends on the absolute mean effective gain (MEG) and the change in correlation due to AIM; In cases where AIM has little impact on correlation, the mean incident angles with high AIM gains were close to those with high MEGs.
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| 26. |
- Vasilev, Ivaylo, et al.
(författare)
-
Measured adaptive matching performance of a MIMO terminal with user effects
- 2013
-
Ingår i: IEEE Antennas and Wireless Propagation Letters. - 1548-5757. ; 12, s. 1720-1723
-
Tidskriftsartikel (refereegranskat)abstract
- Absorption and impedance mismatch due to the proximity of a user as well as certain propagation channel characteristics can severely degrade the multiple-input multiple-output (MIMO) performance of multi-antenna terminals in real usage scenarios. In this context, we investigated the potential of adaptive impedance matching (AIM) to mitigate performance degradation from these effects based on channel measurements involving a terminal prototype in three user scenarios and two propagation environments. First, optimal AIM state for the terminal in a given user-channel setup was found by post-processing the measured channels. The optimal state was then experimentally verified with two Maury Microwave mechanical tuners. The results show that by employing AIM instead of 50Ω termination, the average capacity is increased by up to 25%. Moreover, the observed capacity gains can be partly explained by physical mechanisms underlying the propagation conditions. Furthermore, the achieved gains with real tuners are only marginally affected by the tuners’ actual insertion losses, estimated to be 0.1-0.7 dB. Therefore, we conclude that AIM can be a viable solution to enhance MIMO terminal performance.
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| 27. |
- Vasilev, Ivaylo, et al.
(författare)
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On user effect compensation of MIMO terminals with adaptive impedance matching
- 2013
-
Ingår i: IEEE International Symposium on Antennas and Propagation, 2013. - 1947-1491 .- 1522-3965. ; , s. 174-175
-
Konferensbidrag (refereegranskat)abstract
- Proximity of user has been established as a major cause of performance degradation in multiple-input multiple-output (MIMO) terminals. Here, we investigate the potential of adaptive impedance matching (AIM) to improve the performance of two MIMO terminals in a free space (FS) and a two-hand (TH) user scenario, assuming uniform 3D angular power spectrum for the incoming signal. The results show that lossless uncoupled AIM circuits can enhance the MIMO capacity of the terminals by up to 43% relative to standard 50 ohm terminations. In particular, the largest capacity gain is obtained in the terminal with good matching but narrower antenna bandwidth and worse isolation performance, for the TH scenario. On the other hand, the terminal with poorer matching but higher isolation and significantly larger bandwidth has lower average capacity in FS. However, it is more robust to user proximity, and hence it achieves only 8% capacity gain with AIM in the TH scenario. Therefore, antenna design parameters can significantly influence potential benefits of AIM in practice.
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| 28. |
- Wernehag, Johan, et al.
(författare)
-
A 30dBm PA for MTC Communication in 65nm CMOS Technology
- 2016
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Ingår i: 2016 IEEE 7th Latin American Symposium on Circuits & Systems (LASCAS). - 9781467378352 ; , s. 147-150
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Konferensbidrag (refereegranskat)abstract
- In this paper the feasibility of using a fully integrated 65nm CMOS PA in future machine-type communication standards has been investigated. The integrated PA investigated shows a linear output power in VSWR 2:1 of minimum 24dBm. A VSWR of 2:1 with an associated 3.1dB front-end insertion loss corresponds to a VSWR of 5:1 at the antenna, which is a conservative number. The PAE at 1dB compression point is close to 40% for VSWR 1:1. Taking margin for modulation peak-to-average ratio of 5dB, the PAE at compression point -5dB is 31% at 2100MHz and 24% at 2600MHz. To show the possibility of multi-band operation the PA is centered at 2100MHz and then retuned to 2600MHz, indicating feasibility of a single high band PA. The gain of the two-stage PA is 27dB at 2100MHz and 24dB at 2600MHz. All simulated with a 3.3V output stage supply.
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| 29. |
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| 30. |
- Ying, Zhinong, et al.
(författare)
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Diversity antenna terminal evaluation
- 2005
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Ingår i: IEEE Antennas and Propagation Society, AP-S International Symposium (Digest). - 1947-1491 .- 1522-3965. - 0780388836 ; 2 A, s. 375-378
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Konferensbidrag (refereegranskat)abstract
- Simulated and measured correlation and diversity performance for a couple of two-antenna concepts are presented. The results indicate that the three-dimensional isotropic incident field is a good reference case to evaluate diversity performance in a multi-antenna application.
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