  Detection of radio emission from exoplanets can provide information on the
star-planet system that is difficult to study otherwise, such as the planetary
magnetic field, magnetosphere, rotation period, interior structure, atmospheric
dynamics and escape, and any star-planet interactions. Such a detection in the
radio domain would open up a whole new field in the study of exoplanets.
However, currently there are no confirmed detections of an exoplanet at radio
frequencies. In this study, we search for non-thermal radio emission from the
55 Cnc system which has 5 known exoplanets. According to theoretical
predictions 55 Cnc e, the innermost planet, is among the best targets for this
search. We observed for 18 hours with the Low-Frequency Array (LOFAR) Low Band
Antenna in the frequency range 26-73 MHz with full-polarization and covered 85%
of the orbital phase of 55 Cnc e. During the observations four digital beams
within the station beam were recorded simultaneously on 55 Cnc, nearby "empty"
sky, a bright radio source, and a pulsar. A pipeline was created to
automatically find and mask radio frequency interference, calibrate the
time-frequency response of the telescope, and to search for bursty planetary
radio signals in our data. Extensive tests and verifications were carried out
on the pipeline. Analysis of the first 4 hours of these observations do not
contain any exoplanet signal from 55 Cnc but we can confirm that our setup is
adequate to detect faint astrophysical signals. We find a 3$\sigma$ upper limit
for 55 Cnc of 230 mJy using the pulsar to estimate the sensitivity of the
observations and 2.6 Jy using the time-series difference between the target and
sky beam. The full data set is still under-going analysis. In the near future
we will apply our observational technique and pipeline to the most promising
exoplanet candidates for which LOFAR observations have already been obtained.
