In future smart cities (SCs) highly developed and smart wireless communication access infrastructures will be needed for the connection of a huge number of different types of objects, sensors and user terminals. Such access networks must have the necessary autonomic and intelligent mechanisms to respond to the needs of an increasing variety of users (human and non-human), to cope with the high user density in SCs, their mobility, new and increasing service requirements, traffic dynamics, SC complex wireless channel conditions, etc. The wireless AN of a future SC must be a type of network which is able to offer revolutionary services, capabilities, and facilities that are hard to be provided via the heterogeneous network (HetNet) infrastructures that are implemented today. This paper introduces the concept of the unified wireless access (UWA) for SCs and considers some of the challenges related to its functional requirements and design. The structure of a sample UWA network illustrating the functional relations between its components is given. It is envisaged that such UWA architecture will perform and could be considered from the aspect of a large scale complex and intelligent cyber physical system (CPS) with control feedbacks and different types of users introducing stochasticity in the loop of the system. For the goal of analyzing the performance and functional relationships between the elements of such UWA a general modeling approach is introduced taking into consideration some of the basic approaches applied for CPS analysis.