Mid Sweden University

The necessity for engineers to stay updated on current technology trends, new technological breakthroughs, and the latest tools is obvious, as is the skill to disseminate new insights to colleagues and peers. Today, there is also a significant amount of material available on the Internet, including guides, tutorials, and online courses. Based on this need, we have developed a new type of course that we offer just before the final thesis project, where our students can set up their own in-depth learning projects and taking their first steps towards lifelong learning. For materials, they can freely choose anything they find appropriate, as long as they can justify their choice well. However, students often choose various MOOC courses as the basis for their projects. The course is student-centered and fully adapted to a flipped classroom model, with minimal teaching effort, focusing on students learning from each other in various seminars. The result has been a course highly appreciated by students, which has created electiveness and depth with minimal teaching efforts, as well as maturity in preparation for their upcoming independent work and their professional roles. And finally, hopefully a good start to their lifelong learning as professionals.

In this work, we will present the course setup we have run over the past 4 years for our engineering students. Including the courses details and how we have actively developed the course. Hence, in this work we have investigated the following two research questions:1) How can we teach our engineering students to initiate lifelong learning?2) How can we create valuable electives with little teaching effort towards the end of our engineering program?

Our course is in the form of a self-study where students themselves set up their own learning project, focus, learning objectives, theoretical tasks, and practical tasks. The results have been very successful, and the students have shown a deep understanding of learning on their own, how to learn, how they can communicate what they have learned to their colleagues in various good ways, and enabled electiveness if it is something they feel was missing in their engineering education or if it is something they want to delve deeper into. As well as an acceleration towards their thesis work and the opportunity to study a little extra beforehand, in the specific subject that their future thesis work will address. We have run the course for 4 semesters now for a total of 44 students and the students have gone through about 40 different courses and books. Resulting in a very appreciated course and good grades in our evaluations, as well as student throughput as high as 93%.

Our primary conclusions are that we have succeeded well in teaching students to learn on their own and thus start lifelong learning as professionals. And that we have shown that we can with small means and teacher time create good depth and valuable electiveness for our students. Our future work lies in refining and clarifying the demands on their work to reach different grades, and work with adjusting the examination form to not rely as much on the report itself in grading. Hence, we are optimistic about the future of this course and since the students themselves choose their areas, the course keeps itself updated on future trends and we teachers only need to follow along on the journey.

Vi har tagit fram en modern läskurs i seminarieform, där studenterna själva sätter upp ett självstudieprojekt genom att dra nytta av MOOC-kursmaterial. Vår kurs avser att ge civilingenjörsstudenter erfarenhet av denna typ av online-kursmaterial och på så sätt förbereda dem på ett framtida livslångt lärande. Kursen ger även fördjupningsmöjligheter inom många fler områden än lärosätet kan erbjuda konventionella kurser. Vidare syftar kursen till att förmedla både teoretiska kunskaper och praktiska färdigheter som förberedelse inför utbildningens avslutande självständiga arbete, samt att möjliggöra specialisering som start på en framtida karriärväg. Vi har med små lärarinsatser skapat detta kursupplägg, genom att tillämpa studentcentrerat lärande och flipped classroom-tekniker. Studenterna kompletterar ofta MOOC-kurserna med djupare teoriuppgifter, positionerar ämnet vetenskapligt, och reflekterar över sitt lärande i en slutrapport. Vi examinerar hur väl de har planerat och genomfört sina självstudier. Kursen har erbjudits för fyra årskullar. Genomströmning har varit 93% och den har fått goda omdömen i kursutvärderingar. Eftersom studenterna kan välja mellan ett stort antal MOOC kurser som ständigt utvecklas, och studenterna brukar välja aktuella ämnen, så håller kursen sig själv uppdaterad inför framtida trender. Vi lärare behöver endast följa med på resan och får kompetensutveckling inom nya områden på köpet.

The multi-hop ad-hoc networking paradigm isexpected to be a key feature in future wireless communicationsystems. In a typical data broadcast scenario, multi-hop ad-hocrouting protocols allow devices (called nodes in this paper) tocommunicate and form networks in a manner to enable them tosuccessfully communicate and share information with all othernodes. To ensure maximum reachability in a multi-hop network,the concept of cooperative diversity, in which multiple nodescooperate to transmit the same data to a destination, can beapplied. The cooperative diversity is best exploited with the use ofSingle Frequency Networks (SFNs), also known as a form ofMacro-diversity. This work comprises of a design and analysis ofan SFN based distributed cooperative routing protocol (SFNDCRP)for multi-hop ad-hoc networks with a focus on routinginitiation phase with CSMA as a synchronization mechanism. Theproposed protocol is proactive and incurs minimum per packetdelay. The total delay in routing initiation phase for a network ofn nodes is identified as a problem of n2+2n. A delivery rate orreachability improvement of up-to 36% points for a node isobserved for the SFN based protocol as compared to a non-SFNbased protocol. For synchronization, a CSMA MAC protocol isdeployed for which a deficiency of only less than 0.1 percent existsin the measurements due to collisions in the network.

In the terrestrial digital TV systems DVB-T/H/T2, broadcasting is employed, meaning that all TV programs are sent over all transmitters, also where there are no viewers. This is inefficient utilization of spectrum and transmitter equipment. Applying interactive multicasting over DVB-T2 is a novel approach that would substantially reduce the spectrum required to deliver a certain amount of TV programs. Further gain would be achieved by Dynamic single-frequency network (DSFN) formations, which can be implemented using the concept of PARPS (Packet and Resource Plan Scheduling). A Zipf-law heterogeneous program selection model is suggested. For a system of four coordinated transmitters, and certain assumptions, IP multicasting over non-continuous transmission DSFN gives 1740% increase in multiuser system spectral efficiency (MSSE) in (users∙bit/s)/Hz/site as compared to broadcasting over SFN.

A new approach to improving the energy consumption and node reachability of multihop networks is to dynamically combine multihop routing with single-frequency networks (transmitter macrodiversity), i.e. several nodes sending the same signal simultaneously over the same frequency channel. Four routing algorithms are suggested and evaluated for a broadcasting scenario. Simulation results show that the best algorithm reduces the energy consumption by up to 42% in comparison to non-SFN multihop routing for the same node reachability. SFN-based multihop routing improves the reachability by up to 37 percentage points as compared to non-SFN routing. A 3.8 dB diversity gain is observed that allows a 54% higher data rate for the same bit error probability. By restricting the SFN sizes to a maximum number of nodes, the energy efficiency may be improved while the reachability is deteriorated.

A novel idea presented in this paper is to combine multihop routing with single-frequency networks (SFNs) for a broadcasting scenario. An SFN is a set of multiple nodes that transmit the same data simultaneously, resulting in transmitter macrodiversity. Two of the most important performance factors of multihop networks, node reachability and routing robustness, are analyzed. Simulation results show that our proposed SFN-D routing algorithm improves the node reachability by 37 percentage points as compared to non-SFN multihop routing. It shows a diversity gain of 3.7 dB, meaning that 3.7 dB lower transmission powers are required for the same reachability. Even better results are possible for larger networks. If an important node becomes inactive, this algorithm can find new routes that a non-SFN scheme would not be able to find. Thus, two of the major problems in multihopping are addressed; achieving robust routing as well as improving node reachability or reducing transmission power.

Wireless asymmetric Internet access with a downlink peak bit rate of 10 to 30 Mb/s can be achieved by using the terrestrial digital video broadcasting system (DVB-T) as a supplemental downlink together with today's cellular systems. This paper is a study of dynamic radio resource management on a packet-by-packet basis for this broadband downlink. The dynamic single frequency networks (DSFN) scheme is evaluated. It exploits the macrodiversity capability of the OFDM modulation scheme. The transmitters are dynamically divided into groups of transmitters that send the same information at the same channel frequency simultaneously. The fairly shared spectrum efficiency (FSSE), in bits per second per Hertz per site, which is a combined measurement of maximum throughput and fairness, is evaluated for best-effort traffic. DSFN improves the FSSE by 100% to 370%, for a certain set of test cases, in comparison to the dynamic packet assignment (DPA) scheme, which combines packet scheduling with dynamic channel assignment (DCA).

The OFDM based terrestrial digital video broadcasting system (DVB-T) can be utilized for asymmetric Internet access with a downlink peak bit rate of 10-20Mbps. A narrow-band cellular communications system can be used as uplink. This paper is a comparison of centralized dynamic radio resource management schemes for this downlink packet radio system. Spectrum efficiency in bit/s/Hz/transmitter, and fairly shared spectrum efficiency in bit/s/Hz/transmitter, are evaluated for a best-effort traffic snapshot model. The Dynamic Packet Assignment (DPA) algorithm performs combined packet scheduling and rapid Dynamic Channel Allocation. Even better performance is achieved by the Dynamic Single Frequency Networks (DSFN) scheme. It exploits the macro-diversity capability of OFDM modulation. The base station transmitters are dynamically divided into groups that send the same information at the same channel frequency simultaneously.

The Terrestrial Digital Video Broadcasting system (DVB-T) can be utilized as a supplemental broadband downlink to today´s cellular systems. Thus, mobile Internet access with downstream peek bit rates of 10 to 30 Mbit/s can be achieved. To make this concept competitive in comparison to for example UMTS, efficient Radio Resource Management (RRM) is essential. Schemes for downlink dynamic RRM on a packet-by-packet basis are suggested and evaluated for a simplified packet data model. Packet and Resource Plan Scheduling (PARPS) schemes reduce the problem of finding an optimized combination of several RRM parameters to a scheduling problem. Dynamic Single Frequency Networks (DSFN) and Virtual Cellular Networks (VCN) exploits the macro-diversity capability of the OFDM modulation scheme by dynamically forming groups of transmitters that send the same information on the same frequency channel simultaneously. Dynamic Packet Assignment (DPA) is a combination of Dynamic Channel Assignment (DCA) and packet scheduling. The Fairly Shared Spectrum Efficiency (FSSE), in bit/s/Hz/transmitter site, is improved by up to 370% for a certain test cases, by the DSFN scheme in comparison to DPA.

By combining a cellular system with the terrestrial digital video broadcasting system (DVB-T), wide-area asymmetric Internet access can be achieved, with a downlink peak bit rate of 10-20Mbps. In this paper, we study dynamic resource management on a packet-by-packet basis for this broadband downlink. A model for best-effort traffic is proposed, which simplifies the evaluation of maximum throughput and fairness. Dynamic Single Frequency Networks (DSFN) are evaluated, which exploits the macrodiversity capability of the OFDM modulation scheme. The transmitters are divided into single frequency networks (SFNs), i.e. groups of transmitters that send the same information at the same channel frequency simultaneously. An algorithm changes the SFN grouping from timeslot to timeslot, and schedules the packets. DSFN is a way of introducing timeslots and Dynamic Channel Allocation into DVB-T, without keying of the transmitter power. Thus, receiver and transmitter circuits existing on the market today can be used, and only software modifications are required. A spectrum efficiency of 0.45 bit/s/Hz/site is achieved with omni-directional antennas under certain conditions. This is a capacity improvement of 170% in comparison to a Fixed Channel Allocation solution with static handover.