l transmit power calibration to reduce interference towards co-channel macro-users UE-based Linear interference Interference suppression by means of linear interference suppression combining of received signals at the UE mitigation antennas, for example, interference rejection combining (IRC) Non-linear interference The UE estimates and reconstructs the interfering suppression signal(s) followed by subtraction before decoding the desired signal. Also includes elements of network assistance for some cases between macro and/or small cells has gained significant interest and is used for enhanced inter- cell interference coordination (eICIC) and coordinated multipoint (CoMP) or enhanced CoMP (eCoMP) as will be explained in greater details in this chapter. It is furthermore worth noticing that frequency-domain inter-cell interference management on a physical resource block (PRB) resolution can be realized with channel-aware frequency-selective scheduler (FSS) without any explicit inter-eNodeB coordination. Downlink eNodeB transmit power control is another apparatus which is used for closed subscriber group (CSG) femtocells to reduce the generated interference from such cells towards nearby users that are not allowed access, that is, users that are not having a matching CSG cell identity. As will be discussed in greater details in the forth- coming sections, the full potential of the network-based interference coordination options is unleashed by conducting fast inter-cell coordination in coherence with the time-variant traffic fluctuations in the network. Furthermore, the UE also offers powerful mechanisms for handling interference. UEs with more than one antenna (M > 1) can exploit linear interference suppression techniques such as minimum mean square error interference rejection combining (MMSE-IRC) as standard- ized in Release 11 in the form of UE performance requirements for M = 2. In theory, a UE with M antennas have N = M - 1 degrees of freedom that can be used for either suppress- ing N interfering streams or d