  The Tunka-Rex experiment (Tunka Radio Extension) has been deployed in 2012 at
the Tunka Valley (Republic of Buryatia, Russia). Its purpose is to investigate
methods for the energy spectrum and the mass composition of high-energy cosmic
rays based on the radio emission of air showers. Tunka-Rex is an array of 25
radio antennas distributed over an area of 3 km^2. The most important feature
of the Tunka-Rex is that the air-shower radio emission is measured in
coincidence with the Tunka-133 installation, which detects the Cherenkov
radiation generated by the same atmospheric showers. Joint measurements of the
radio emission and the Cherenkov light provide a unique opportunity for cross
calibration of both calorimetric detection methods. The main goal of Tunka-Rex
is to determine the precision for the reconstruction of air-shower parameters
using the radio detection technique. In this article we present the current
status of Tunka-Rex and first results, including reconstruction methods for
parameters of the primary cosmic rays.
