Methods and apparatus to schedule uplink transmissions in wireless communication
systems, such as cellular communi cation systems, are disclosed. A disclosed example …

(56) References Cited ferent communication networks. The method also includes monitoring
a communication congestion level within the Vir US PATENT DOCUMENTS tual talk group …

A cellular communication system comprising a plurality of user equipment and a network
infrastructure. Radio resource of the plurality of cells is divided into more than one radio …

(57) ABSTRACT A multicell communication system includes a plurality of cells which use a
frequency band on a division basis, wherein a frequency reuse factor K is defined such that …

A spectrum control system according to the present invention includes an identifying unit that
identifies a base station or a cell that does not satisfy a predetermined level of …

(57) ABSTRACT A method for managing virtual talk groups includes facilitat ing
communications from a plurality of endpoints via an interoperability system. The plurality of …

In a case where a second reference signal for a second com munication system is
transmitted in addition to a first refer ence signal for a first communication system, resources …

A transmitter includes a bandwidth configuration unit configured to provide an increased
system bandwidth corresponding to a bandwidth extension over multiple component …

H04L 5/00(2006.01)(57) ABSTRACT H04L 27/26(2006.01) H04. I4/00(2006.01) HO47
(6/12(2006.01) In a method for communicating by radio, a frequency band (52) US …

US PATENT DOCUMENTS FOREIGN PATENT DOCUMENTS 6,011,851 A 1/2000
O'Connor et al............... 381.17 EP 1622 408 A1 2, 2006 6,094,578 A 7/2000 Purcell et al …