  In this paper, we propose an optimization method for the broadcast rate in
vehicle-to-vehicle (V2V) broadcast communications at an intersection on the
basis of theoretical analysis. We consider a model in which locations of
vehicles are modeled separately as queuing and running segments and derive key
performance metrics of V2V broadcast communications via a stochastic geometry
approach. Since these theoretical expressions are mathematically intractable,
we developed closed-form approximate formulae for them. Using them, we optimize
the broadcast rate such that the mean number of successful receivers per unit
time is maximized. Because of the closed form approximation, the optimal rate
can be used as a guideline for a real-time control-method, which is not
achieved through time-consuming simulations. We evaluated our method through
numerical examples and demonstrated the effectiveness of our method.
