Microwave Technology about Joakim Johansson

Joakim Johansson was appointed Adjunct Professor in Microwave Technology in October 2002. Born in Töllsjö, Sweden in 1959, he was awarded an MScEng, Lic. Eng., and Ph.D. in electrical engineering from Chalmers in 1983, 1986 and 1988 respectively. In 1886-87 he spent six months as a visiting scholar at the University of Massachusetts at Amherst, Massachusetts USA. He was an assistant professor at the Department of Radio and Space Science at Chalmers until 1994, pursuing research on millimetre and sub-millimetre wave radio astronomy instrumentation. Since 1994 he has been employed by Ericsson Microwave Systems AB, Mölndal, Sweden, where he is a Senior Specialist in Sensor Antenna Systems. His main area of work is R&D in antenna systems for future radar systems. He is also Programme Director at Chalmers for the International MSc programme Hardware for Wireless Communications. Z6s5M{mE  
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Summary of the research qd2xb8r  
Joakim Johansson's primary research interest has always been in the antenna field. During his years at the Department of Radio and Space Science at Chalmers the main research topics were quasi-optical components and systems for millimetre and sub-millimetre wave radio astronomy instrumentation. The main 'customers' for this research were the Onsala Space Observatory and the Sweden-ESO Sub-millimetre Telescope (SEST). He was also involved in pre-studies for the Swedish research satellite Odin. His main area of work at Ericsson has been research projects aimed at providing demonstrators for antenna systems for radar systems of the future. These systems will to a large extent comprise large antenna arrays with hundreds of modules in antenna-integrated microwave technology. Ol+Kp!ocY  
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Interview for "New Knowledge" ZwJciT!_~  
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Our knowledge of microwave technology has led to a minor revolution. With the aid of microwaves we can, for example, prepare food and speak on wireless telephones. 'EX4.h a5  
Joakim Johansson is working on the latest generation of radar. Forget those mechanically revolving radar antennas; in the future they will take the form of small tiles. WmVVR>0V|  
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He says that it feels a little like returning to the family home. Granted he hasn’t been farther away than Mölndal and Ericsson but nevertheless. After graduating with an MSCEE from Chalmers, followed by a PHD and a number of years as an assistant professor, Joakim Johansson had not grown tired of research; he simply saw the position at Ericsson’s R&D department for antenna systems as a continuation. VTw/_Hf2p  
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“The best thing about working there was moving between two different parts of the organisation: research and product development. Previously I also worked with civilian mobile communication but now I work mostly with radar for military use.” Antennas, particularly in close association with transmitters and receivers, have for a long time been Joakim Johansson’s specialisation. At Ericsson Microwave he is what is known as a senior specialist. (_8#YyW#  
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“Generally speaking, the borders between different units within microwave technology are being erased. Transmitters and receivers are now to be found in one single unit and we no longer call it radar but sensors, as radar is only one of several possible functions for the system. My task is to keep track of the subject and the research situation within radar antenna technology, to gather knowledge and to pass on this knowledge to designers and other interested parties. As specialists, of which there are a number in various areas, we act as a kind of strategic resource to ensure that Sweden does not lag behind.” PZOORjF8A  
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A great deal of the research required to maintain Sweden’s position can be performed by Ericsson itself although there are always gaps, particularly within basic research, that cannot be covered. The specialist area of antennas and radar is very technology-intensive and complex, with approximately ten years between initial concept and product application. The most recent technology, which is currently being tested in certain systems, is a different kind of radar, with probably ten years before it can be produced, sold and used in practice – in aircraft for example. )U98  
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“Instead of one transmitter there are 1,000 pieces fitted onto tiles. Each tile also has an antenna and a receiver. In doing so, everything can be controlled much more easily and effectively. It can be said that the whole process comprises three stages. The first stage is to make the antennas electronically scanned, the second is to make them active, i.e. giving each antenna element its own transmitter and receiver, and the third stage is to digitise the signals that are received and then perform all signal processing on the computer. Parts of these three stages are already in use but up to now not all in the same system. The system replaces the old, mechanically revolving radar antenna. The advantage is the enormous flexibility. The radar can stop at a certain desired point to then carry on without any mechanical inertia. An image can be generated constantly without needing to wait for it to turn another revolution.” zixEMi[8  
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Even more forward-thinking ideas are of course in the pipeline but they will have to wait for a while before they can be aired with the academics at Microelectronics. Initially, Joakim Johansson’s time at Chalmers will be taken up with his work as programme director for the newly-started international Master’s programme in microwave technol-ogy ‘Hardware for wireless communications’. The programme deals with microwave technology in all its forms, specialising in the hardware itself – all the parts that make up a wireless communication system. KTmaglgp  
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A relatively large part of the course takes the form of a project where the students, in groups of six, assume responsibility for the whole arrangement and perform tasks assigned to them at a company, giving them much-needed training in the lead-up to working life. j$PI,
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“We have been involved in planning for roughly one and a half years. Whilst there is naturally a great deal of work to be done initially it is highly stimulating to meet students again. I have worked a good deal with lectures and in-house training at Ericsson and I have a certain degree of experience. The difference here at Chalmers is, as always, that the students are at times rather quiet. We have noticed, however, that the foreign stude .. 5si}i'in  
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