  Arrays of imaging air Cherenkov telescopes (IACTs) like VERITAS, HESS have
been recently proposed as the instruments of the next generation for ground
based very high energy gamma-ray astronomy invading into 50-100 GeV energy
range. Here we present results of design studies for the future IACT arrays
which have been performed by means of Monte Carlo simulations. We studied
different trigger strategies, abilities of cosmic ray rejection for arrays of 4
and 16 telescopes with 10 m reflectors, equipped with cameras comprising 271
and 721 pixels of 0.25 and 0.15 degree, respectively. The comparative analysis
of the performance of such telescope arrays has been done for both camera
options, providing almost the same field of view of 4.3 degree. An important
issue is the choice of the optimum spacing between the telescopes in such an
array. In order to maximize the signal-to-noise ratio in observations at the
small zenith angles of 20 degree as well as at large zenith angles of 60
degree, different arrangements of IACT array have been examined. Finally, we
present a major recommendations regarding the optimum configuration.
