A method performed by a network node (10; 20 A; 20B; 20C) for allocating Time Transmission Intervals, TTI, during uplink transmission, said network node (10; 20A; 20B; 20C) being one of several network nodes (10; 20A; 20B; 20C) in a shared radio cell environment and serving a first radio cell and control the other network nodes (10; 20A; 20B; 20C) in the shared radio cell environment, which other network nodes (10; 20A; 20B; 20C) are serving other radio cells, each network node (10; 20A; 20B; 20C) serving a group of User Equipments, UEs, for uplink transmission and each network node (10; 20A; 20B; 20C) acting as a serving network node (10; 20A; 20B; 20C) for all UEs in the group served by said network node (10; 20A; 20B; 20C) and as a listening network node (10; 20A; 20B; 20C), for UEs served by other network nodes (10; 20A; 20B; 20C), if said network node (10; 20A; 20B; 20C) receives UE transmissions from UEs served by other network nodes (10; 20A; 20B; 20C), said method comprising: determining, for each serving network node (10; 20A; 20B; 20C) if it also acts as listening network node (10; 20A; 20B; 20C) for UEs not served by this serving network node (10; 20A; 20B; 20C), and allocating TTls such that the UE transmission for UEs having both a serving network node (10; 20A; 20B; 20C) and one or more listening network nodes (10; 20A; 20B; 20C) is coordinated by scheduling said UE transmission in the same TTI frame for the serving network node (10; 20A; 20B; 20C) and said one or more listening network nodes (10; 20A; 20B; 20C) in the shared radio cell environment; characterized in that the method further comprises: determining which network node (10; 20A; 20B; 20C) acting as both serving network node (10; 20A; 20B; 20C) and as listening network node (10; 20A; 20B; 20C) within the shared radio cell environment that receives most UE transmissions, and allocating TTIs for all UEs, for which this determined network node (10; 20A; 20B; 20C) is either the serving network node (10; 20A; 20B; 20C) or the listening network node (10; 20A; 20B; 20C), prior to allocating TTls for UEs of all other network nodes (10; 20A; 20B; 20C) in the shared radio cell environment. determining, for each serving network node (10; 20A; 20B; 20C) if it also acts as listening network node (10; 20A; 20B; 20C) for UEs not served by this serving network node (10; 20A; 20B; 20C), and allocating TTls such that the UE transmission for UEs having both a serving network node (10; 20A; 20B; 20C) and one or more listening network nodes (10; 20A; 20B; 20C) is coordinated by scheduling said UE transmission in the same TTI frame for the serving network node (10; 20A; 20B; 20C) and said one or more listening network nodes (10; 20A; 20B; 20C) in the shared radio cell environment; determining which network node (10; 20A; 20B; 20C) acting as both serving network node (10; 20A; 20B; 20C) and as listening network node (10; 20A; 20B; 20C) within the shared radio cell environment that receives most UE transmissions, and allocating TTIs for all UEs, for which this determined network node (10; 20A; 20B; 20C) is either the serving network node (10; 20A; 20B; 20C) or the listening network node (10; 20A; 20B; 20C), prior to allocating TTls for UEs of all other network nodes (10; 20A; 20B; 20C) in the shared radio cell environment.