D-Band downconversion mixer design in CMOS-SOI

Abstract. The current surge in research interest around the sub-THz frequency region comes as a no surprise. The potential for greater data rates and available bandwidths are just a couple reasons why research around these frequencies should be prioritized. Many viable receiver structures have been presented for these frequency regions, but they all have one thing in common: They all include a downconversion mixer. The mixer is a crucial piece in the receiver structure, converting the higher frequency radio frequency (RF) signal to a much lower intermediate frequency (IF) signal using multiplication with a local oscillator (LO) signal. The resulting waveform is much easier to handle for signal processing that comes after. The downconversion should be able to provide a fair amount of gain to the converted signal on a wide range of input signals, measured with the 1dB compression point. The noise figure is also a major consideration for RF-devices, but in the case of the mixer, its importance is not as prevalent as it is for the LNA that precedes it, since the noise of the mixer is attenuated by the gain of the previous stages. This master’s thesis work introduces the basic theory around downconversion mixers, followed by the design of a mixer from schematic level circuit design all the way to the physical layout. The physical design is done using 22nm FDSOI technology, provided by GlobalFoundries. The design is made for a direct conversion receiver using Gilbert cell topology, meaning image rejection is reasonable and depends only on the received signal itself, and good noise and feedthrough performance should be expected in simulations. The mixer is to downconvert a 151 GHz signal down to 0–1 GHz, using an LO signal between 150–151 GHz. Two iterations of the mixer are shown in the end results, the first one being based on the schematic design, and the second one with adjustments made for better performance. While driving a high impedance 500 Ohm load, the second iteration was able to reach a conversion gain of -10.0 dB with a 1dB compression point of 6.4 dBm while dissipating 4.7 mW of power. DSB noise figure was simulated to be 17.3 dB and the LO leakage to the IF output at -27.7 dBm.Alaspäin taajuusmuuntavan sekoittimen suunnittelu D-kaistalle käyttäen CMOS-SOI teknologiaa. Tiivistelmä. Nykyinen tutkimuksen keskittyminen millimetriaalto ja THz taajuusalueille ei tule kenellekään yllätyksenä. Suurempien datanopeuksien ja vapaiden taajuuskaistojen potentiaali ovat vain joitain monista hyvistä käytännön syistä, miksi tutkimusta näiden taajuuksien ympärillä priorisoidaan. Monia käytännöllisiä vastaanotinrakenteita on esitetty näille taajuusalueille ja niillä on kaikilla yksi yhteinen tekijä: tajuusmuunnin alemmille taajuuksille. Taajuusmuunnin eli sekoitin on olennainen osa vastaanotinrakenteita, muuntaen korkeamman radiotaajuuden (RF) matalammalle välitaajuudelle (IF) käyttäen taajuuksien sekoittamista paikallisoskillaattorilla (LO). Mikserin ulostulosignaali on signaalinprosessoinnin näkökulmasta paljon käytännöllisempi. Alaspäin taajuusmuuntavan mikserin tulee pystyä vahvistamaan laajaa skaalaa erivahvuisia signaaleja, minkä ylärajaa mittaamme 1 dB kompressiopisteellä. Radiolaitteistossa kohinaluku tulee yleensä myös ottaa huomioon, mutta johtuen mikserin sijainnista vastaanotinketjussa, kohinaluku vaimenee suhteessa sitä edeltävien vahvistuksien verran, eikä siksi ole niin kriittinen. Tämä diplomityö esittelee lukijalle ensiksi alaspäin muuntavan taajuussekoittimen perusteorian, toisena sen teoreettisen piirikaavion suunnittelun sekä sen simuloinnin tuloksia, ja viimeisenä fyysisen layoutin suunnittelun sekä sen simuloinnin tulokset. Fyysisen layoutin suunnittelu ja simulointi tehdään käyttäen GlobalFoundries 22nm FDSOI teknologiaa. Suunnittelu tehdään suoramuunnosvastaanottimelle käyttäen Gilbertin solu topologiaa, eliminoiden peilitaajuuksista aiheutuvat ongelmat, sekä vähentäen kohinan sekä ei-haluttujen signaalien läpivuotojen vaikutusta. Sekoittimen tulee muuntaa 151 GHz signaali n. 0–1 GHz kantataajuudelle käyttäen LO-signaalia taajuusvälillä 150–151 GHz. Lopullisissa tuloksissa vertaillaan kahta eri iteraatiota. Ensimmäisenä versiota, joka luotiin alun perin teoriapohjaisen piirisuunnittelun pohjalta, sekä toista versiota, missä useilla parannuksilla mikserin suorituskykyä saatiin parannettua. Korkeaimpedanssista 500 Ohmin kuormaa ajaessa mikseri ylsi -10.0 dB vahvistukseen, 1 dB kompressiopiste oli 6.4 dB kuluttaen 4.7 mW virtaa käytössä. Kohinaluvuksi simuloitiin 17.3 dB, sekä LO signaalin vuodosta IF lähtöön oli -27.7 dBm

LAD- ja WIBA-energiailmaisumenetelmien suorituskyky BPSK-signaalille

Tiivistelmä. Tässä työssä tutkittiin LAD- ja WIBA-energiailmaisumenetelmien suorituskykyjä BPSK-signaalille erilaisissa tilanteissa. Tilanteita olivat signaalin sijainnin muuttaminen suhteessa WIBA-menetelmän ikkunoihin, sekä ilmaisutodennäköisyyden muuttaminen molemmille menetelmille. Lisäksi saatiin tietoa signaalin leveyden vaikutuksesta sekä LAD- että WIBA-menetelmän suorituskykyyn. Tutkimus tehtiin käyttämällä MatLab-ohjelmaa simuloimalla kohinaista BPSK-signaalia. Tutkimuksen motiivina oli tuottaa molemmista ilmaisumenetelmistä käyttö- ja vertailukelpoista dataa, mitä voidaan hyödyntää jatkotutkimuksessa, sekä tulevaisuudessa tietoliikenneverkostojen luotettavuuden parantamisessa. Tuloksista havaittiin WIBA-ikkunan sijoittelulla olevan pieni, enintään noin 1 dB (SNR-tasossa), ero suorituskyvyissä, kun verrattiin huonointa sijoittelua parhaimpaan mahdolliseen. Simuloimalla myös eri signaalin leveyksillä, pystyttiin toteamaan WIBA-menetelmän olevan tehokkaampi kapeilla kaistanleveyksillä. Erot eivät olleet kuitenkaan kovin suuria, vain muutaman desibelin luokkaa. Ilmaisutodennäköisyyden muuttamista tutkittaessa huomattiin erojen olevan käytännössä olemattomat WIBA-signaalille, johtuen signaalin täydellisestä sijoittelusta näissä simulaatioissa. LAD-menetelmän tapauksessa erot olivat merkittäviä. Väljimmästä ilmaisutodennäköisyydestä tiukimpaan oli eroa SNR-tasossa toistuvasti 11–13 dB, riippuen signaalin kaistanleveydestä. LAD-menetelmässä vaadittu SNR-arvo hyvään (Pd=0.9) ilmaisuun nousi lähes 10 dB, kun signaalin kaistanleveys muuttui 5 %:sta 20 %:iin kokonaiskaistanleveydestä.Performance of LAD and WIBA energy detection methods for BPSK signal. Abstract. In this thesis, the performance of LAD and WIBA energy detection methods for a BPSK modulated signal was studied in different environments. The situations included changing the position of the signal in relation to the WIBA-windows and changing the definition of the detection probability for both methods. Additionally, information about the effect of signal width on the performance of both the LAD and WIBA methods was received. The study was performed using MatLab by simulating a BPSK-signal with noise. The motive of the study was to produce usable and comparable data from both detection methods, which can be utilized in further inspection, as well as be used for improving the reliability of telecommunication networks in the future. From the results, it was found that the effects of moving the signal in relation to the WIBA-windows to be small, at most 1 dB (in SNR-level) difference in performance between the worst- and best-case scenario. By simulating different signal widths, it was found that the WIBA-method performs better at narrower signal widths. The differences were not very large, at most a few decibels. While changing the definition of the detection probability, the effects for WIBA-method were found to be insignificant, due to the perfect window positioning. In the case of the LAD method, the changes were significant. Between the loosest and strictest definitions, the difference in SNR-level was repeatedly between 11–13 dB, depending on the signal bandwidth. In the LAD-method the required SNR value for good detection (Pd=0.9) increased by almost 10 dB when the signal bandwidth was increased from 5 % to 20 % of the total bandwidth

Control of VEGF-A transcriptional programs by pausing and genomic compartmentalization.

Vascular endothelial growth factor A (VEGF-A) is a master regulator of angiogenesis, vascular development and function. In this study we investigated the transcriptional regulation of VEGF-A-responsive genes in primary human aortic endothelial cells (HAECs) and human umbilical vein endothelial cells (HUVECs) using genome-wide global run-on sequencing (GRO-Seq). We demonstrate that half of VEGF-A-regulated gene promoters are characterized by a transcriptionally competent paused RNA polymerase II (Pol II). We show that transition into productive elongation is a major mechanism of gene activation of virtually all VEGF-regulated genes, whereas only ∼40% of the genes are induced at the level of initiation. In addition, we report a comprehensive chromatin interaction map generated in HUVECs using tethered conformation capture (TCC) and characterize chromatin interactions in relation to transcriptional activity. We demonstrate that sites of active transcription are more likely to engage in chromatin looping and cell type-specific transcriptional activity reflects the boundaries of chromatin interactions. Furthermore, we identify large chromatin compartments with a tendency to be coordinately transcribed upon VEGF-A stimulation. We provide evidence that these compartments are enriched for clusters of regulatory regions such as super-enhancers and for disease-associated single nucleotide polymorphisms (SNPs). Collectively, these findings provide new insights into mechanisms behind VEGF-A-regulated transcriptional programs in endothelial cells

Factors associated with parental recognition of a child's overweight status - a cross sectional study

<p>Abstract</p> <p>Background</p> <p>Very few studies have evaluated the association between a child's lifestyle factors and their parent's ability to recognise the overweight status of their offspring. The aim of this study was to analyze the factors associated with a parent's ability to recognise their own offspring's overweight status.</p> <p>Methods</p> <p>125 overweight children out of all 1,278 school beginners in Northern Finland were enrolled.</p> <p>Weight and height were measured in health care clinics. Overweight status was defined by BMI according to internationally accepted criteria. A questionnaire to be filled in by parents was delivered by the school nurses. The parents were asked to evaluate their offspring's weight status. The child's eating habits and physical activity patterns were also enquired about. Factor groups of food and physical activity habits were formed by factor analysis. Binary logistic regression was performed using all variables associated with recognition of overweight status in univariate analyses. The significant risk factors in the final model are reported using odds ratios (ORs) and their 95% confidence intervals (CIs).</p> <p>Results</p> <p>Fifty-seven percent (69/120) of the parents of the overweight children considered their child as normal weight. Child's BMI was positively associated with parental recognition of overweight (OR 3.59, CI 1.8 to 7.0). Overweight boys were less likely to be recognised than overweight girls (OR 0.14, CI 0.033 to 0.58). Child's healthy diet (OR 0.22, CI 0.091 to 0.54) and high physical activity (OR 0.29, CI 0.11 to 0.79) were inversely related to parental recognition of overweight status.</p> <p>Conclusions</p> <p>Child's healthy eating habits and physical activity are inversely related to parental recognition of their offspring's overweight. These should be taken into account when planning prevention and treatment strategies for childhood obesity.</p

Laparoscopic ventral rectopexy in male patients with external rectal prolapse is associated with a high reoperation rate

Background Laparoscopic ventral rectopexy has been used to treat male patients with external rectal prolapse, but evidence to support this approach is scarce. The aim of this study was to evaluate the results of this new abdominal rectopexy surgical technique in men. Methods This was a retrospective multicenter study. Adult male patients who were operated on for external rectal prolapse using ventral rectopexy in five tertiary hospitals in Finland between 2006 and 2014 were included in the study. Patient demographics, detailed operative, postoperative and short-term follow-up data were collected from patient registers in participating hospitals. A questionnaire and informed consent form was sent to all patients. The questionnaire included scores for anal incontinence, obstructed defecation syndrome, urinary symptoms and sexual dysfunction. The main outcome measure was the incidence of recurrent rectal prolapse. Surgical morbidity, the need for surgical repair due to recurrent symptoms and functional outcomes were secondary outcome measures. Results A total of 52 adult male patients with symptoms caused by external rectal prolapse underwent ventral rectopexy. The questionnaire response rate was 64.4 %. Baseline clinical characteristics and perioperative results were similar in the responder and non-responder groups. A total of 9 (17.3 %) patients faced complications. There were two (3.8 %) serious surgical complications during the 30-day period after surgery that necessitated reoperation. None of the complications were mesh related. Recurrence of the prolapse was noticed in nine patients (17 %), and postoperative mucosal anal prolapse symptoms persisted in 11 patients (21 %). As a result, the reoperation rate was high. Altogether, 17 patients (33 %) underwent reoperation during the follow-up period due to postoperative complications or recurrent rectal or mucosal prolapse. According to the postoperative questionnaire data, patients under 40 had good functional results in terms of anal continence, defecation, urinary functions and sexual activity. Conclusions Laparoscopic ventral rectopexy is a safe surgical procedure in male patients with external prolapse. However, a high overall reoperation rate was noticed due to recurrent rectal and residual mucosal prolapse. This suggests that the ventral rectopexy technique should be modified or combined with other abdominal or perineal methods when treating male rectal prolapse patients.Peer reviewe

Quantum degeneracy in mesoscopic matter: Casimir effect and Bose-Einstein condensation

The ground-state phonon pressure is an analogue to the famous Casimir pressure of vacuum produced by zero-point photons. The acoustic Casimir forces are, however, many orders of magnitude weaker than the electromagnetic Casimir forces, as the typical speed of sound is 100 000 times smaller than the speed of light. Because of its weakness, zero-point acoustic Casimir pressure was never observed, although the pressure of artificially introduced sound noise on a narrow aperture has been reported. However, the magnitude of Casimir pressure increases as $1/L^3$ with the decrease of the sample size $L$, and reaches picoNewtons in the sub-micron scales. We demonstrate and measure the acoustic Casimir pressure induced by zero-point phonons in solid helium adsorbed on a carbon nanotube. We have also observed Casimir-like "pushing out" thermal phonons with the decreasing temperature or the length. We also show that all thermodynamic quantities are size-dependent, and therefore in the mesoscopic range $L\lesssim\hbar{c}/(k_BT)$ quadruple points are possible on the phase diagram where four different phases coexist. Due to the smallness of solid helium sample, temperature of Bose-Einstein condensation (BEC) of vacancies is relatively high, $10-100$ mK. This allowed us to experimentally discover the BEC in a system of zero-point vacancies, predicted more than 50 years ago

Factors affecting young adults’ willingness to try novel health-enhancing nature-based products

One of the megatrends that affects consumers' preferences is a growing interest in health, well-being and self-care. This study explores consumer perceptions of a health-enhancing nature-based substance. Based on a survey data (N = 944) collected among national and international students in Finland, we examined factors that affect young adults' willingness to try products containing the substance. The results showed a relatively high willingness to try the products, particularly among female and non-Finnish respondents. Relationship to nature and beliefs related to the health benefits or risks of soil microbes influenced willingness to try products. The results highlight the importance of accounting for consumer perceptions in the innovation process.Peer reviewe

Redo ventral rectopexy : is it worthwhile?

Background Minimally invasive ventral mesh rectopexy (VMR) is a widely used surgical treatment for posterior pelvic organ prolapse; however, evidence of the utility of revisional surgery is lacking. Our aim was to assess the technical details, safety and outcomes of redo minimally invasive VMR for patients with external rectal prolapse (ERP) recurrence or relapsed symptoms of internal rectal prolapse (IRP). Methods This is a retrospective cohort study of patients with recurrent ERP or symptomatic IRP who underwent redo minimally invasive VMR between 2011 and 2016. The study was conducted at three hospitals in Finland. Data collected retrospectively included patient demographics, in addition to perioperative and short-term postoperative findings. At follow-up, all living patients were sent a questionnaire concerning postoperative disease-related symptoms and quality of life. Results A total of 43 redo minimally invasive VMR were performed during the study period. The indication for reoperation was recurrent ERP in 22 patients and relapsed symptoms of IRP in 21 patients. In most operations (62.8%), the previously used mesh was left in situ and a new one was placed. Ten (23.3%) patients experienced complications, including 2 (4.7%) mesh-related complications. The recurrence rate was 4.5% for ERP. Three patients out of 43 were reoperated on for various reasons. One patient required postoperative laparoscopic hematoma evacuation. Patients operated on for recurrent ERP seemed to benefit more from the reoperation. Conclusions Minimally invasive redo VMR appears to be a safe and effective procedure for treating posterior pelvic floor dysfunction with acceptable recurrence and reoperation rates.Peer reviewe

Increased Serum PAI-1 Levels in Subjects with Metabolic Syndrome and Long-Term Adverse Mental Symptoms: A Population-Based Study

Depression is an independent risk factor for cardiovascular diseases and is associated with metabolic syndrome (MetS). Levels of plasminogen activator inhibitor-1 (PAI-1), an inhibitor of tissue-type and urokinase-type plasminogen activators, are associated with MetS. To clarify the role of PAI-1 in subjects with long-term adverse mental symptomatology (LMS; including depression) and MetS, we measured circulating PAI-1 levels in controls (n = 111), in subjects with MetS and free of mental symptoms (n = 42), and in subjects with both MetS and long-term mental symptoms (n = 70). PAI-1 increased linearly across the three groups in men. In logistic regression analysis, men with PAI-1 levels above the median had a 3.4-fold increased likelihood of suffering from the comorbidity of long-term adverse mental symptoms and MetS, while no such associations were detected in women. In conclusion, our results suggest that in men high PAI-1 levels are independently associated with long-term mental symptomatology