tion including asymmetrical implementation of the option in the downlink and uplink (e.g., option 7-1 in the uplink and option 7-2 in the downlink). A compression technique may 5G Network Architecture 73 be applied to reduce the required transport bandwidth between the CU and the DU. This option will allow traffic aggregation from NR and LTE transmission points to be cen- tralized and can facilitate the management of traffic load between NR and LTE trans- mission points. This option can to some extent relax the fronthaul throughput requirements and allows centralized scheduling and joint processing in both transmit and receive sides. However, it may require subframe-level timing synchronization between the fragmented parts of physical layer in the CU and the DUs. The following represent different forms where this option can be implemented: Option 7-1: In this variant, the fast Fourier transform (FFT), CP removal (OFDM processing), and possibly PRACH processing is implemented in the uplink and in the DUs, and the remaining physical layer functions reside in the CU. In the down- link, inverse FFT (IFFT) and CP insertion blocks (OFDM processing) reside in the DUs and the rest of physical layer functions will be performed in the CU. This vari- ant would allow implementation of advanced receivers. Option 7-2: In this variant, FFT, CP removal, resource de-mapping, and possibly MIMO decoding functions are implemented in the DU in the uplink and the remain- ing physical layer functional processing are performed in the CU. In the downlink, IFFT, CP addition, resource mapping, and MIMO precoding functions are per- formed in the DU, and the rest of physical layer processing is performed in the CU. This variant also allows the use of advanced receivers for enhanced performance. Option 7-3: This downlink only option implements the channel encoder in the CU, and the rest of physical layer functions are performed in the DU(s). This option can reduce the fronthaul throughput requirements as the payloads consist of the encoded bi