System and method for non-contention based handover based on pre-reserved target cell uplink allocations in communication systems

#The present invention is directed, in general, to communication systems and, in an exemplary embodiment, to a system and method for performing handover in a communication system.

#The communication of information is a necessity of modern society, which is enabled through the operation of a communication system. Information is communicated between a sending station and a receiving station by way of a communication channel. The sending station converts the information into a form for communication over the communication channel. The receiving station detects and recovers the information for the benefit of a user. A wide variety of different types of communication systems have been developed and are regularly employed to effectuate communication between sending and receiving stations.

#An exemplary communication system is a cellular communication system in which a communication channel is defined upon a radio link extending between sending and receiving stations. Cellular radio communication systems are amenable to implementation as mobile communication systems wherein radio links, rather than fixed, wireline connections, are employed to define communication channels.

#For a more complete understanding of the invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawing, in which:

#FIGS. 1 to 4 illustrate system level diagrams of communication systems including wireless communication systems that provide an environment for application of the principles of the present invention;

#FIGS. 5 and 6 illustrate block diagrams of embodiments of a user equipment and a base station of a communication system in accordance with the principles of the present invention;

#The making and using of the presently preferred embodiments are discussed in detail below. It should be appreciated, however, that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed are merely illustrative of specific ways to make and use the invention, and do not limit the scope of the invention.

#The present invention will be described with respect to exemplary embodiments in a specific context of coordinating allocation of resources for user equipment to be handed over from a source base station to a target base station without contention and without a need for sharing timing information therebetween. In general, embodiments of the invention may be applied to any form of communication system and network such as a cellular wireless communication system and network.

#The Third Generation Partnership Project Long Term Evolution (“3GPP LTE”) is the name generally used to describe an ongoing effort across the industry to improve the universal mobile telecommunications system (“UMTS”) for mobile communications to cope with continuing new requirements and the growing base of users. Goals of this broadly based project include improving communication efficiency, lowering costs, improving services, making use of new spectrum opportunities, and achieving better integration with other open standards. The 3GPP LTE project is not itself a standard-generating effort, but will result in new recommendations for standards for the UMTS.