  Tunka-Rex is a new radio antenna array which extends the Tunka experiment in
Siberia close to lake Baikal. It consists of 20 antennas on an area of 1 km^2
which measure the radio emission of high-energy air showers. Tunka-Rex is
triggered by the photomultiplier array of Tunka measuring air-Cherenkov light
of air showers in the energy range from about 10 PeV to 1 EeV. This
configuration allows for the worldwide first hybrid measurements of the radio
and air-Cherenkov signal for the same events: an ideal situation to perform a
cross-calibration between both methods. Consequently, the main goal of
Tunka-Rex is to determine the achievable energy and Xmax precision of radio
measurements by comparing them to the reconstruction of the air-Cherenkov
measurements. Tunka-Rex started operation in autumn 2012, and already detected
air-shower events. In this paper we present the status of Tunka-Rex and first
results which indicate that Tunka-Rex measures indeed the radio emission by air
showers and that is is sensitive to their energy.
