  The main advantage of Microwave Kinetic Inductance Detector arrays (MKID) is
their multiplexing capability, which allows for building cameras with a large
number of pixels and good sensitivity, particularly suitable to perform large
blank galaxy surveys. However, to have as many pixels as possible it is
necessary to arrange detectors close in readout frequency. Consequently KIDs
overlap in frequency and are coupled to each other producing crosstalk. Because
crosstalk can be only minimised by improving the array design, in this work we
aim to correct for this effect a posteriori. We analysed a MKID array
consisting of 880 KIDs with readout frequencies at 4-8 GHz. We measured the
beam patterns for every detector in the array and described the response of
each detector by using a two-dimensional Gaussian fit. Then, we identified
detectors affected by crosstalk above -30 dB level from the maximum and removed
the signal of the crosstalking detectors. Moreover, we modelled the crosstalk
level for each KID as a function of the readout frequency separation starting
from the assumption that the transmission of a KID is a Lorenztian function in
power. We were able to describe the general crosstalk level of the array and
the crosstalk of each KID within 5 dB, so enabling the design of future arrays
with the crosstalk as a design criterion. In this work, we demonstrate that it
is possible to process MKID images a posteriori to decrease the crosstalk
effect, subtracting the response of each coupled KID from the original map.
