A retrial system with constant attempts

In this article we study a retrial queueing system in which customers in orbit join a queue with a FIFO discipline. We use the process (M(t),N(t) where M(t) represents the number of arrivals during a elapsed service time until t while N(t) stands for the random number of customers in orbit al time t. We obtain the probabitity in the steady state in the M/M/1 case. The joint generating function in the M/G/1 case is also studied