Activities for the square kilometer array (SKA) in Europe

The paper is an overview of the activities in research and development of the new generation radio telescope, the SKA, in Europe. It focuses on the aperture array technology for decameter and longer wavelengths, including relevant actions for the low frequency array (LOFAR) and focal plane arrays (FARADAY) covering the lower and higher frequency bands. We describe the concepts, specifications and the key parameters as well as application directions for radioastronomy for SKA, FARADAY and LOFAR.