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Home energy technologies, such as smart home energy management systems (SHEMS), are important in reducing energy-related emissions and empowering energy users. However, there are concerns on gender inclusiveness of the adoption and use of SHEMS. So far, information systems research has failed to address this significant challenge. This study examines factors shaping gendered adoption and use of smart home technologies, particularly SHEMS, and the implications this has for sustainability and energy equality. Applying a critical lens, we examine findings from a sensory ethnographic study on the adoption of SHEMS in households. The findings underline the need for more inclusive energy technology design, more understanding of diversity of households and more variety in the approaches for increasing awareness on and facilitating the adoption of energy technologies. We contribute to research on gender and home energy technologies, and to the larger discussion of gender and energy.

Cognitive functioning is a relevant work and health related topic, however, validated methods to assess subjective cognitive complaints (SCC) at work are lacking. We introduce the Cognitive Function at Work Questionnaire (CFWQ) for measuring SCC in occupational settings. 1-year follow-up data of 418 employees from a Finnish public media service company was analyzed. Participants completed web-based CFWQ, cognitive tests and a broad set of questionnaires for evaluating depression, anxiety, insomnia, daytime sleepiness, burnout, stress, mental job burden, work ability, cognitive errors, and perceived health. The factor analysis yielded a model with the CFWQ subdomains: Memory, Language, Executive Function, Speed of Processing, Cognitive Control and Name Memory. The internal consistency (Cronbach’s alpha = 0.87) and the test-retest constancy (ICC = 0.84) reflected good reliability. Correlation between the CFWQ and cognitive errors at work ranged from 0.25 to 0.64 indicating adequate concurrent validity. Employees with depression, insomnia and burnout symptoms had higher (p < 0.001) CFWQ scores than participants without these symptoms. Depression and burnout symptom severity as well as accumulation of mood, sleep, and psychosocial stressors were associated with higher CFWQ scores (p < 0.001 in all). The CFWQ appears psychometrically sound measure for the assessment of SCC in occupational population.

Collecting data from Internet-of-Things (IoT) devices, especially the variety of sensors dispersed in the environment, is an increasingly important and difficult task. Several long-range radio-access technologies, such as low-power wide-area networks (LPWAN) and specifically LoRaWAN, have been proposed to address this challenge. However, until now, the key focus of the related studies has been on static terrestrial LPWAN deployments. In this study, we depart from this vision and investigate the practical feasibility and performance of a LoRaWAN gateway (GW) on a flying platform, specifically — an unmanned aerial vehicle (UAV). The key contributions of this study are (i) the design and field-testing of a packet-sniffer-based mobile LoRaWAN GW prototype, allowing collection of the data from LoRaWAN networks, including the already deployed ones; (ii) the open-publication of the data collected during our experimental campaign in the 426 LoRaWAN sensor node network of the University of Oulu illustrating the performance of different drone trajectories; (iii) the initial results of the system’s performance analysis, revealing some interesting trends and setting goals for further studies, and pinpointing the lessons learned during the experimental campaign. Our empirical findings suggest that the Travelling Salesman Problem (TSP) trajectory is the most effective moving trajectory for the number of packets collected and the average energy consumed per packet collected.

Smart spaces, physical spaces that are integrated with sensor-enabled IoT devices, are a powerful paradigm for optimizing the operations of the space and improving its quality for the occupants. Managing the applications and services running in the space is a complex task as the operations of the devices and services are dependent on the physical characteristics of the space, the occupants of the space, and the technologies that are being integrated. Digital twinning, the combination of physical representations with a virtual counterpart, is a potential technology for facilitating the management of smart space devices and services. While digital twins are increasingly adopted in industry, their use in everyday environments remains low due to difficulties in creating and linking the virtual representation with the physical environment. In this paper, we propose our vision for the adoption of digital twinning as a pathway to improve the functions of smart spaces. We derive a generic reference architecture that comprises four layers, covering the physical space, the sensing infrastructure, the network interfaces, and the underlying computational infrastructure. Next, we identify and address key requirements for the uptake of digital twins in smart space and assess their benefits using the ascendancy model of business analytics. Finally, to demonstrate the practicality of digital twinning, we present a proof-of-concept digital twin for the TellUs smart space at the University of Oulu in Finland and use it to highlight the potential benefits of different ascendancy levels.

Tiivistelmä Väestön vanhetessa muistisairauksien varhaiseen tunnistamiseen perusterveydenhuollossa tarvitaan paljon lisää resursseja. Kognitiivinen tehtäväsarja CERAD on osoittautunut hyvin toimivaksi välineeksi Alzheimerin taudin ensivaiheen arvioinnissa. Koulutus ja ikä vaikuttavat kognitiivisissa testeissä suoriutumiseen, joten ne on tärkeää huomioida tulosten tulkinnassa. Tehtäväsarjaan on päivitetty koulutustason huomioivat katkaisurajat sekä uutena kokonaispistemäärän käyttö.

Introduction: Lifetime exposure to occupational complexity is linked to late-life cognition, and may affect benefits of preventive interventions. Methods: In the 2-year multidomain Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER), we investigated, through post hoc analyses (N = 1026), the association of occupational complexity with cognition. Occupational complexity with data, people, and substantive complexity were classified through the Dictionary of Occupational Titles. Results: Higher levels of occupational complexity were associated with better baseline cognition. Measures of occupational complexity had no association with intervention effects on cognition, except for occupational complexity with data, which was associated with the degree of intervention-related gains for executive function. Discussion: In older adults at increased risk for dementia, higher occupational complexity is associated with better cognition. The cognitive benefit of the FINGER intervention did not vary significantly among participants with different levels of occupational complexity. These exploratory findings require further testing in larger studies.

We aimed to evaluate the feasibility of using real-world register data for identifying persons with mild Alzheimer’s disease (AD) and to describe their cognitive performance at the time of diagnosis. Patients diagnosed with AD during 2010–2013 (aged 60–81 years) were identified from the Finnish national health registers and enlarged with a smaller private sector sample (total n = 1,268). Patients with other disorders impacting cognition were excluded. Detailed clinical and cognitive screening data (the Consortium to Establish a Registry for Alzheimer’s Disease neuropsychological battery [CERAD-nb]) were obtained from local health records. Adequate cognitive data were available for 389 patients with mild AD (31%) of the entire AD group. The main reasons for not including patients in analyses of cognitive performance were AD diagnosis at a moderate/severe stage (n = 266, 21%), AD diagnosis given before full register coverage (n = 152, 12%), and missing CERAD-nb data (n = 139, 11%). The cognitive performance of persons with late-onset AD (n = 284), mixed cerebrovascular disease and AD (n = 51), and other AD subtypes (n = 54) was compared with that of a non-demented sample (n = 1980) from the general population. Compared with the other AD groups, patients with late-onset AD performed the worst in word list recognition, while patients with mixed cerebrovascular disease and AD performed the worst in constructional praxis and clock drawing tests. A combination of national registers and local health records can be used to collect data relevant for cognitive screening; today, the process is laborious, but it could be improved in the future with refined search algorithms and electronic data.

Introduction: Lifestyle interventions may prevent cognitive decline, but the sufficient dose of intervention activities and lifestyle changes is unknown. We investigated how intervention adherence affects cognition in the FINGER trial (pre-specified subgroup analyses). Methods: FINGER is a multicenter randomized controlled trial examining the efficacy of multidomain lifestyle intervention (ClinicalTrials.gov NCT01041989). A total of 1260 participants aged 60 to 77 with increased dementia risk were randomized to a lifestyle intervention and control groups. Percentage of completed intervention sessions, and change in multidomain lifestyle score (self-reported diet; physical, cognitive, and social activity; vascular risk) were examined in relation to change in Neuropsychological Test Battery (NTB) scores. Results: Active participation was associated with better trajectories in NTB total and all cognitive subdomains. Improvement in lifestyle was associated with improvement in NTB total and executive function. Discussion: Multidomain lifestyle changes are beneficial for cognitive functioning, but future interventions should be intensive enough, and supporting adherence is essential.

During the past years, the LoRaWAN technology took a prominent position among the wireless connectivity solutions for the Internet of Things (IoT) and has attracted substantial attention. The LoRaWAN technology has become popular for collecting the data from the sensors, which traditionally have periodic communication patterns. Meanwhile, recent studies have shown that the LoRaWAN procedures, such as the over-the-air activation, may also compromise the uniformity of data traffic distribution. Therefore, in this study, we investigate how the communication pattern of LoRaWAN devices during activation and data communication affects the overall network performance with respect to speed of activation and overall packet delivery probability. We show that the periodic communication patterns, widely employed by commercial LoRaWAN devices today, are less efficient than the patterns featuring random delays between the packets. Also, we find that introduction of a random delay between uplink data packets helps randomizing the channel access and enables network performance boost both for the application data transfer and during the activation. Finally, we show that implementation of the suggested communication patterns modification is feasible for the state-of-the-art LoRaWAN transceivers with no hardware modifications.

Background and aims: Psychosocial factors may affect adherence to lifestyle interventions and lifestyle changes. The role of psychosocial factors in dementia prevention needs more research. We aimed at clarify the issue in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER). Methods: The population included 1260 participants aged 60–77 years at risk for cognitive decline, randomised to a multidomain lifestyle intervention or regular health advice for 2 years. Adherence was evaluated as participation in the provided activities and actual lifestyle changes, separately for each domain (diet, exercise, social/cognitive activity, vascular risk management) and combined into multidomain. Psychosocial factors were measured at trial baseline (depressive symptoms; study perception; health-related quality of life, HRQoL) and earlier life (hopelessness; satisfaction with family life, achievements, and financial situation). Results: Depressive symptoms, hopelessness, and nonpositive study perception were negatively and HRQoL positively associated with participation in the multidomain intervention. Depressive symptoms, lower HRQoL, hopelessness and dissatisfaction with financial situation were associated with unhealthier lifestyles at baseline. Baseline depressive symptoms and lower HRQoL predicted less improvement in lifestyle, but did not modify the intervention effect on lifestyle change. Discussion and conclusions: Several psychosocial factors were associated with participation in lifestyle intervention, while fewer of them contributed to lifestyle changes. Although the intervention was beneficial for lifestyle changes independent of psychosocial factors, those most in need of lifestyle improvement were less likely to be active. Tailoring lifestyle-modifying strategies based on the need for psychosocial support may add efficacy in future trials.

Depression and cognition are associated, but the role of depressive symptoms in lifestyle interventions to prevent dementia needs further study. We investigated the intervention effect on depressive symptoms and their associations with cognition in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER; NCT01041989), a two-year multidomain lifestyle trial. One thousand two-hundred and sixty individuals (60–77 years) at risk for dementia were randomised into a multidomain intervention (diet, exercise, cognitive training, and vascular/metabolic risk monitoring) or control group (regular health advice). Depressive symptoms (Zung scale) and cognition (modified Neuropsychological Test Battery) were evaluated at baseline, 12, and 24 months. One thousand one-hundred and twenty-five participants had baseline Zung data. Mean Zung score decreased 0.73 (SD 5.6) points in the intervention and 0.36 (5.6) points in the control group, with nonsignificant between-group difference (group × time coefficient −0.006, 95% CI −0.019 to 0.007). Overall, higher baseline Zung score was associated with less improvement in global cognition (−0.140, p = 0.005) and memory (−0.231, p = 0.005). Participants with clinically significant baseline depressive symptoms (Zung ≥ 40 points) had less intervention benefit to executive functioning (group × time × Zung −0.096, 95% CI −0.163 to −0.028). Change in Zung score was not associated with change in cognition. Clinically significant depressive symptoms warrant more attention when designing dementia-prevention interventions.

Background: Shorter leukocyte telomere length (LTL) is associated with aging and dementia. Impact of lifestyle changes on LTL, and relation to cognition and genetic susceptibility for dementia, has not been investigated in randomized controlled trials (RCTs). Methods: Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability is a 2-year RCT enrolling 1260 participants at risk for dementia from the general population, aged 60–77 years, randomly assigned (1:1) to multidomain lifestyle intervention or control group. The primary outcome was cognitive change (Neuropsychological Test Battery z-score). Relative LTL was measured using quantitative real-time polymerase chain reaction (trial registration: NCT01041989). Results: This exploratory LTL substudy included 756 participants (377 intervention, 379 control) with baseline and 24-month LTL measurements. The mean annual LTL change (SD) was −0.016 (0.19) in the intervention group and −0.023 (0.17) in the control group. Between-group difference was nonsignificant (unstandardized β-coefficient 0.007, 95% CI −0.015 to 0.030). Interaction analyses indicated better LTL maintenance among apolipoprotein E (APOE)-ε4 carriers versus noncarriers: 0.054 (95% CI 0.007 to 0.102); younger versus older participants: −0.005 (95% CI −0.010 to −0.001); and those with more versus less healthy lifestyle changes: 0.047 (95% CI 0.005 to 0.089). Cognitive intervention benefits were more pronounced among participants with better LTL maintenance for executive functioning (0.227, 95% CI 0.057 to 0.396) and long-term memory (0.257, 95% CI 0.024 to 0.489), with a similar trend for Neuropsychological Test Battery total score (0.127, 95% CI −0.011 to 0.264). Conclusions: This is the first large RCT showing that a multidomain lifestyle intervention facilitated LTL maintenance among subgroups of older people at risk for dementia, including APOE-ε4 carriers. LTL maintenance was associated with more pronounced cognitive i

In this paper, GNSS-Reflectometry is performed using Unmanned Aerial Vehicle (UAV). Received GNSS multipath signal is utilized to perform environment remote sensing in dynamic and static flight modes. Right-Hand Circular Polarized (RHCP) multipath signal is recorded and its interference frequency is used to estimate the height of UAV above the ground surface. In the dynamic flight mode, the C/N0 level of the reflected Left-Hand Circular Polarized (LHCP) signal is used to indicate the presence of different ground surfaces. In comparison with the ground measurement systems, UAV provides a dynamic and flexible measurement platform, potentially significantly reducing the measurement time. At the same time, measurement signal quality is influenced due to the variation of the UAV altitude. The results presented strongly indicate the possibility of utilizing UAVs as measurement platform for remote sensing using GNSS multipath signal.

Introduction: Web‐based cognitive tests have potential for standardized screening in neurodegenerative disorders. We examined accuracy and consistency of cCOG, a computerized cognitive tool, in detecting mild cognitive impairment (MCI) and dementia. Methods: Clinical data of 306 cognitively normal, 120 mild cognitive impairment (MCI), and 69 dementia subjects from three European cohorts were analyzed. Global cognitive score was defined from standard neuropsychological tests and compared to the corresponding estimated score from the cCOG tool containing seven subtasks. The consistency of cCOG was assessed comparing measurements administered in clinical settings and in the home environment. Results: cCOG produced accuracies (receiver operating characteristic‐area under the curve [ROC‐AUC]) between 0.71 and 0.84 in detecting MCI and 0.86 and 0.94 in detecting dementia when administered at the clinic and at home. The accuracy was comparable to the results of standard neuropsychological tests (AUC 0.69–0.77 MCI/0.91–0.92 dementia). Conclusions: cCOG provides a promising tool for detecting MCI and dementia with potential for a cost‐effective approach including home‐based cognitive assessments.

Primary progressive aphasia (PPA) forms the spectrum of language variants of frontotemporal lobar degeneration (FTLD), including three subtypes each consisting of distinctive speech and language features. Repeat expansion in C9orf72 gene is the most common genetic cause of FTLD. However, thus far only little is known about the effects of the C9orf72 repeat expansion on the phenotype of PPA. This retrospective study aimed at determining the differences between the PPA phenotypes of the C9orf72 expansion carriers and non-carriers. Our results demonstrated no significant differences between these groups, indicating that the C9orf72 repeat expansion does not substantially affect the phenotype of PPA.

The current trend of delivering goods is to use lockers located close to the customers. The locker needs to communicate with a delivery system, which is most convenient to achieve with wireless technologies. There are mechanical, industrial design and reliability advantages to place a radio unit inside of the locker. However, it is challenging from a radio communication perspective, especially with conducting door material like metal. In this work, RF radiation performance from inside of the metallic locker with two different door materials was studied. The studied RF frequencies cover operational frequencies of LTE NBIoT, Sigfox, LoRa, Wifi, and 5G NR at 3.5 GHz. The simulations and measurements show that the radiation pattern of the metal door locker resemble radiation pattern of array. The main radiation direction with metal doors can be backside of the locker, while with a wood laminate the primary radiation direction is toward front side of the locker.

Background:Subjective memory complaints (SMCs) may be the first sign of cognitive decline in aging. Objective:To examine whether SMCs reported by oneself and informant predict cognitive change over 2 years among at-risk elderly people, and to determine the relationship of different types of SMCs (prospective and retrospective memory complaints) and change in cognitive function. Methods:This investigation is part of the FINGER project, which is a multicenter randomized controlled trial aiming at preventing cognitive decline in cognitively healthy older adults with increased risk of dementia. A subsample of 303 control-group participants (aged 60–80 years) and their informants (n = 261) rated the frequency of SMCs, using the Prospective and Retrospective Memory Questionnaire (PRMQ). Cognitive performance was measured at baseline and at 1- and 2-year follow-up visits using a neuropsychological test battery. Results:Participants who reported more SMCs improved less in global cognition, executive function, and memory during the subsequent 2 years in the fully-adjusted analyses. Self-reported retrospective memory problems predicted less improvement in all cognitive domains, whereas prospective memory problems did not. Informant-reported memory problems were not linked to subsequent change in cognition. Conclusion:Our results indicate that self-reported SMCs, measured with PRMQ, predict future cognitive change in several cognitive domains. By contrast, reports by informants were not linked to changes in cognition. Among cognitively healthy at-risk elderly individuals, the persons themselves observe more easily problems relevant for their future cognitive trajectories than their informants.

Tiivistelmä Suomessa toteutettu FINGER-tutkimus tarjoaa toimintamallin maailmanlaajuisen muistisairausepidemian hillitsemiseksi. Monimuotoinen ohjelma voi pienentää muistihäiriöiden riskiä jopa 30 %. Ohjelman kulmakivet ovat käytännönläheinen ravitsemusohjaus, nousujohteinen liikuntaharjoittelu, muistiharjoittelu sekä sydän- ja verisuonitautien riskitekijöiden hallinta. Muistisairauksien ehkäisyn toimintamalli tulisi integroida nykyisiin sydän- ja verisuonitautien ja diabeteksen ehkäisytoimiin., The Finnish Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) was globally the first randomized controlled trial showing that intensive lifestyle intervention targeting simultaneously several modifiable dementia-related risk factors has beneficial effects on the cognition of older persons who are at increased risk for cognitive decline. FINGER intervention included simultaneous nutritional guidance, physical exercise, cognitive training and social activities, and management of vascular risk factors. The control group received regular health advice. FINGER results showed that persons in the intervention group had a 30% lower risk for cognitive decline during the 2-year intervention compared with the control group. Beneficial effects were also seen for physical functioning and quality of life. Successful FINGER intervention serves as a model for effective dementia prevention. The model should be integrated into existing cardiovascular disease and diabetes prevention strategies.

We propose a carefully selected receiver structure, detector and detector implementation architecture for multiple-input multiple-output (MIMO) uplink base station receiver for fourth generation (4G) wireless cellular systems. First, we compare different receiver algorithms and structures for single-carrier frequency-division multiple access (SC-FDMA) uplink transmission to get a good understanding of the performance and complexity of these algorithms and their suitability for practical realization. One of those structures, namely the frequency domain MMSE equalization with sphere detection (SD), is proposed for implementation. The receiver consists of separate stages for inter-symbol interference (ISI) and inter-antenna interference (IAI) mitigation in frequency selective MIMO channels. Frame error rate (FER) performance is studied via simulations in realistic wireless channels and practical system parameters. K-best SD is selected as a detector algorithm for this receiver. There are several publications proposing a sort-free architecture for tree search type of detectors. Both a conventional K-best architecture and a sort-free architecture are implemented on a Xilinx Virtex-6 field-programmable gate array (FPGA) using High Level Synthesis (HLS) tool. Both architectures support 4 × 4 MIMO with 64-level modulation (64-QAM). Complexity results confirm that avoiding the sorter is not always recommended. The benefit of sort-free architecture depends on the system parameters.

Introduction: Association between healthy diet and better cognition is well established, but evidence is limited to evaluate the effect of dietary changes adopted in older age. Methods: We investigated the role of dietary changes in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) with 1260 at-risk participants (60–77 years) who were randomized to intensive multidomain intervention (including dietary counseling) or regular health advice for 2 years. Parallel process latent growth curves of adherence to dietary recommendations and cognitive performance were analyzed. Results: Adherence to healthy diet at baseline predicted improvement in global cognition, regardless of intervention allocation (P = .003). Dietary improvement was associated with beneficial changes in executive function, especially in the intervention group (P = .008; P = .051 for groups combined). Discussion: Dietary changes initiated during the intervention were related to changes in executive function in 2 years. Long-term diet appeared more influential for global cognition.

In this paper, we implement a high throughput multiple-input multiple-output (MIMO) detector for single-carrier frequency-division multiple access (SC-FDMA) base station. High-level Synthesis (HLS) tool is used for implementing the algorithm on Xilinx Virtex and Zynq FPGAs. First, we compare the throughput performance and power consumption results of the different implementations. Second, we evaluate the quality of the results by comparing the HLS results to handwritten register-transfer level (RTL) implementations. In conclusion, the HLS tools have evolved into applicable implementation tools. Furthermore, the possible slight losses in the performance or design complexity with the HLS design method could be counteracted by choosing a higher category FPGA.

Introduction: The 2-year Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) multidomain lifestyle intervention trial (NCT01041989) demonstrated beneficial effects on cognition. We investigated whether sociodemographics, socioeconomic status, baseline cognition, or cardiovascular factors influenced intervention effects on cognition. Methods: The FINGER recruited 1260 people from the general Finnish population (60–77 years, at risk for dementia). Participants were randomized 1:1 to multidomain intervention (diet, exercise, cognition, and vascular risk management) and regular health advice. Primary outcome was change in cognition (Neuropsychological Test Battery z-score). Prespecified analyses to investigate whether participants’ characteristics modified response to intervention were carried out using mixed-model repeated-measures analyses. Results: Sociodemographics (sex, age, and education), socioeconomic status (income), cognition (Mini–Mental State Examination), cardiovascular factors (body mass index, blood pressure, cholesterol, fasting glucose, and overall cardiovascular risk), and cardiovascular comorbidity did not modify response to intervention (P-values for interaction > .05). Conclusions: The FINGER intervention was beneficial regardless of participants’ characteristics and can thus be implemented in a large elderly population at increased risk for dementia.

The demand in mobile broadband communications is increasing dramatically. It is expected that 1000 times more mobile-network capacity will be needed within 10 years. Multiple-input, multiple-output (MIMO) antenna configuration and spatial multiplexing are among the essential techniques for reaching the targets. This creates motivation for study of advanced receivers for combating inter-antenna interference (IAI) and inter-symbol interference (ISI). While various receiver structures have been extensively considered for MIMO receivers, the emphasis has been on those operating in downlink orthogonal frequency-division multiple access (OFDM) systems, wherein ISI is not a problem. Advanced receiver structures for single-carrier frequency-division multiple access (SC-FDMA) uplink systems were studied and analysed. Various receivers were compared via MATLAB simulations, with the objective being to gain solid understanding of how they perform in different channel environments. An efficient combination of IAI and ISI equalisation for SC-FDMA receivers is proposed. The proposed receiver architecture is shown to be a considerable improvement over the conventional linear minimum mean-square error (LMMSE) receiver. Several MIMO detector algorithms and their performance–complexity characteristics are presented. The K-best algorithm with a list size of 8 is shown to be the best option for practical MIMO detector implementation of this receiver in the 4x4 MIMO 64-level quadrature amplitude modulation (QAM) scenario. The second objective involved examining the implementation aspects of the 8-best receiver to achieve good understanding of the complexity of various implementation architectures. It emerged that avoiding the sorting operation in the 8-best list sphere detector (LSD) tree-search algorithm implementation is not recommendable in the 4x4 MIMO 64-QAM scenario. Several field-programmable gate array (FPGA) implementations were carried out, with a range of high-level s, Tiivistelmä Tiheään asuttujen kaupunkien uudet langattomat palvelut tarvitsevat tietoliikenneverkkoja, jotka mahdollistavat suuremman tiedonsiirtonopeuden ja kapasiteetin kuin sen, jonka nykyiset mobiiliverkot voivat tarjota. On arveltu, että mobiiliverkkojen kapasiteetin tarve tuhatkertaistuu seuraavan kymmenen vuoden aikana. Tuhatkertainen kapasiteetti on arvioitu saavutettavan kasvattamalla kolmea eri osa-aluetta kymmenkertaiseksi: taajuusspektrin määrä, spektrin käytön tehokkuus sekä tukiasematiheys. Tämä väitöskirja keskittyy spektrin käytön tehokkuuden kasvattamiseen. Moniantennitoteutus (multiple-input multiple-output, MIMO) on siinä välttämätön. MIMO-tekniikkaa hyödyntävien solukkojärjestelmien tukiasemavastaanottimissa tarvitaan melko monimutkainen kanavakorjain sekä ilmaisin, joiden algoritmien optimointi ja toteutus ymmärretään vielä sangen puutteellisesti. Väitöskirjatutkimuksen päätavoitteena on tutkia edistyksellisiä vastaanotinrakenteita, joilla saavutetaan LTE-A-standardin tavoitetiedonsiirtonopeus kohtuullisella kompleksisuudella. Työssä keskitytään ns. nousevaan siirtosuuntaan (uplink) eli päätelaitteesta tukiasemaan tapahtuvaan tiedonsiirtoon, jossa käytetään yhden kantoaallon taajuusjakomonikäyttötekniikkaa (single-carrier frequency-division multiple-access, SC-FDMA) ortognaalisen taajuusjakomonikäytön (orthogonal frequency division multiple access, OFDMA) sijaan. Eri vastaanotinrakenteita ja näiden ilmaisinalgoritmeja vertaillaan tietokonesimuloinnein MATLAB-ympäristössä. Väitöskirjassa ehdotetaan kaksiosaista vastaanotinrakennetta, jossa antennien välinen keskinäishäiriö (inter antenna interference, IAI) ja symbolien välinen keskinäisvaikutus (intersymbol interference, ISI) poistetaan kahdessa eri vaiheessa. Tietokoneimulaatiot osoittavat ko. rakenteen parantavan suorituskykyä huomattavasti perinteiseen lineaariseen keskineliövirheen minimoivaan (linear minimum mean square error, LMMSE) vastaanottimeen verrattuna. Nk. K parasta polkua valitseva

In this paper, we describe a spectrum access system (SAS) based Citizens Broadband Radio Service (CBRS) field trial using a live LTE network in the 3.5 GHz band. The latest WInnForum specification guided the implementation of the relevant protocols for SAS operation. Here, we evaluate the performance of a CBRS field trial by using one of the most important performance indicators in a spectrum sharing scenario — the evacuation time. It indicates how rapidly the secondary user relinquishes the shared spectrum band to the primary user. Following the applied protocols, we measure and analyze the time scales for the evacuation and frequency change procedures in a field trial environment. Our work shows that the set time limits for the protection of primary users against interference are realistic when using commercially available mobile networks and equipment. Finally, utilizing knowledge of the latest base station models, we propose ways to reduce the evacuation and reconfiguration time by up to 70%.

In 2011, we proposed a new receiver structure called Frequency domain linear MMSE filter with sphere detection for single-carrier frequency-division multiple access (SC-FDMA) uplink transmission. Frame error rate simulations and complexity estimations were used to define the most practical sphere detector algorithm for this receiver. High-level Synthesis (HLS) tools were used for comparing different architectures for the sphere detector. After 2011, the HLS design approach has gained more popularity and the tools have evolved. In this paper, HLS tools from different generations were used for implementing the same K-best list sphere detector. The results were compared and the overall experience of the optimization process and the evolution of the HLS tools was discussed. Additionally, the evolution of FPGA technology was discussed. In conclusion, the HLS tools have evolved into practical implementation tools even for high complex wireless communication algorithms. Moreover, 25% increase in throughput and 58% lower resource usage was achieved with the latest generation FPGA.

Recently, the Federal Communications Commission has proposed to create Citizens Broadband Radio Service (CBRS) with the three-tier spectrum sharing system to release more spectrum for the mobile broadband usage in the United States. At the moment, the Wireless Innovation Forum is involved in defining the operational and functional requirements for this framework based on [1], and also in standardizations. Evidently, the successful operation of this system depends on efficient channel allocation algorithms. In this paper, we consider the CBRS with the three-tier spectrum sharing system. A set of CBRS users, i.e., Priority Access License (PAL) and General Authorized Access (GAA) users are located in an area, which is divided into multiple census tracts. The PAL and GAA users request frequency channels from the spectrum access system (SAS). The role of the SAS is to allocate channels to these two types of users while providing interference protection to the incumbent users. For this setup, we consider the problem of channel allocation for PAL and GAA users. The objective is to allocate channels for these two types of users, while considering the channel allocation rules proposed in [1]. For this problem, we propose a channel allocation algorithm to be used by the SAS. The proposed algorithm allocates channels to the CBRS users in two steps: 1) allocate channels to the PAL users and 2) allocate channel to the GAA users. Numerically, we show that the proposed algorithm is able to allocate channels while satisfying the rules proposed in [1]. More importantly, this research provides new insights on investigating channel allocation algorithms in CBRS/SAS.

Frontotemporal lobar degeneration (FTLD) is the second commonest cause of dementia after Alzheimer’s disease (AD) in patients <65 years. Its most frequent clinical subtype is behavioral variant frontotemporal dementia (bvFTD) characterized by behavioral change and executive deficits. FTLD also encompasses two variants of primary progressive aphasia (PPA) characterized by language deficits. The majority of familial FTLD cases are linked to the C9ORF72 expansion mutation. As both cognitive and behavioral changes are core diagnostic features of FTLD, neuropsychological assessment is vital. However, neuropsychological literature is inconclusive regarding the most functional measures for detecting FTLD. Current knowledge on the cognitive profile of patients with the C9ORF72 expansion is scarce. The aims of this thesis were threefold: (1) to identify the cognitive measures that optimally serve the differential diagnosis of FTLD, (2) to characterize the neuropsychological profile of C9ORF72 expansion; and (3) to examine the utility of the Modified Frontal Behavioral Inventory (FBI-mod) in differentiating FTLD, AD, and mild cognitive impairment (MCI). The participants comprised FTLD, AD, and MCI patients diagnosed in the University Hospitals of Oulu and Kuopio. The patients underwent a detailed neuropsychological assessment including the CERAD neuropsychological battery (CERAD-NB) and the FBI-mod. While bvFTD was characterized by verbal fluency, working memory, and verbal comprehension deficits relative to AD, AD was associated with greater episodic memory impairments. The poorer delayed recall in AD was further evident on the memory tests of the CERAD-NB; however, its overall utility in the differentiation between FTLD and AD was limited. The C9ORF72 expansion carriers showed more severe executive deficits than non-carriers. The C9ORF72 expansion may further be associated with slowly progressing FTLD. On the FBI-mod, bvFTD was linked to amplified behavioral sym, Tiivistelmä Otsa-ohimolohkorappeumat on Alzheimerin taudin (AT) jälkeen yleisin työikäisten dementiaa aiheuttava sairausryhmä. Sen yleisin alamuoto on otsalohkodementia, jonka ensioireita ovat käyttäytymisen muutokset ja toiminnanohjauksen ongelmat. Sairausryhmään kuuluu myös kaksi kielellisin oirein ilmenevää alatyyppiä. C9ORF72-toistojaksomutaation on todettu selittävän suurimman osan perinnöllisistä tapauksista. Kognitiivisten ja käyttäytymiseen liittyvien muutosten arvioiminen on keskeinen osa taudin diagnostiikkaa. Tutkimustiedon perusteella on epäselvää, mitkä neuropsykologiset menetelmät soveltuvat parhaiten otsa-ohimolohkorappeumien tunnistamiseen. Tieto C9ORF72-mutaation kantajien kognitiivisesta profiilista on niukkaa. Tutkimuksen tavoitteena oli löytää neuropsykologisia menetelmiä, joista on hyötyä otsa-ohimolohkorappeumien erotusdiagnostiikassa ja selvittää C9ORF72-mutaation kantajien neuropsykologisia erityispiirteitä. Lisäksi haluttiin tutkia käytösoireita kartoittavan FBI-mod -läheiskyselyn hyödyllisyyttä otsa-ohimolohkorappeumien, AT:n ja lievän kognitiivisen heikentymän (MCI) erottamisessa. Aineisto koostui Oulun ja Kuopion yliopistosairaaloissa diagnosoiduista otsa-ohimolohkorappeuma-, AT- ja MCI-potilaista, joille oli tehty CERAD-tehtäväsarja, laaja neuropsykologinen tutkimus sekä FBI-mod. Otsalohkodementiaa sairastavat suoriutuivat AT-potilaita heikommin sanasujuvuutta, työmuistia ja kielellistä käsityskykyä arvioivissa tehtävissä, kun taas tapahtumamuisti oli heikompi AT:a sairastavilla. Myös CERAD-tehtäväsarjassa AT-potilaat suoriutuivat heikommin viivästetyn mieleenpalautuksen tehtävissä, mutta kokonaisuutena tehtäväsarjan kyky erotella otsa-ohimolohkorappeumaa ja AT:a sairastavat oli rajallinen. C9ORF72-mutaation kantajilla toiminnanohjauksen ongelmat olivat vaikeampia kuin ei-kantajilla. Lisäksi havaittiin, että C9ORF72-mutaatioon liittyvä sairaus voi edetä hyvin hitaasti. FBI-mod erotteli hyvin otsalohkodementiaa sairastavat AT- ja MCI-poti