 of the GP depends on many factors. First, it should be sufficiently large SO that the eNBs and the radio device get enough time to switch from downlink to uplink. Second, the GP must be long enough to ensure that there is no interference between uplink and downlink transmission. To minimize interference, within a cluster of eNBs, the same subframe configuration is applied across all eNBs. Such a configuration ensures that all these eNBs are either transmitting or receiv- ing at the same time. However, this simultaneous operation means that the eNBs must be accurately synchronized to avoid a UL transmission interfering with a DL transmission from an adjacent eNB. 3GPP (TS 36.133) has specified that the neighboring eNBs must be phase aligned to within 3 us for smooth handover and to avoid any kind of interference between eNBs. Cell Search and Synchronization Cell search is a method for a device to acquire time and synchronization information (transmitted by every radio frame) when the UE initially attaches to the LTE system. When a device or UE at- taches to the system, it synchronizes with the OFDM symbol, slot, subframe, half-frame, and radio frames using the synchronization signals. Each eNB is differentiated by a unique identifier called the cell ID, which is not really unique and can be reused on multiple eNBs if they are placed far enough apart. Two synchronization signals are defined for this purpose: The primary synchronization signal (PSS) The secondary synchronization signal (SSS) These two signals are used in combination to reduce the complexity of the cell search process. The UE first decodes the PSS and SSS to determine the cell ID of the nearest eNB. The UE also ac- quires information on the carrier frequency, frame timing, CP length, and duplex mode. The UE can then request resources for uplink transmission and establish uplink synchronization with the new eNB. Because PSS and SSS signals are transmitted periodically, the UE can continually utilize them. UE to BS Synchronization (TDD) In the precedi