e stays connected to the network with reduced throughput. The receiver is turned on at specific times for updates. For this purpose, both LTE and 5G/NR power save protocols include Discontinuous Reception (DRX) and Discontinuous Transmission (DTX). Both involve reducing transceiver duty cycle while in active operation. DRX also applies to the RRC_Idle state with a longer cycle time than active mode. However, DRX and DTX do not operate without a cost: the UE's data throughput capacity is reduced in proportion to power savings. The RRC sets a cycle where the UE is operational for a certain time when all the schedul- ing and paging information are transmitted. The base station knows that the UE is completely turned off and is not able to receive anything. Except when in DRX, the UE radio must be active to monitor PDCCH (to identify DL data). During DRX, the UE radio can be turned off. Semi-persistent scheduling Semi-persistent scheduling (SPS) involves the base station dedicating resources for transmis- sion and/or reception (independently) over multiple TTIs or slots. SPS is unique per cell and configured by the RRC layer by means of an indication of the UE identifier [Radio Network Temporary Identifier (RNTI)], periodicity, number of associated HARQ processes, and time/ frequency resources (for the uplink case). The purpose of SPS is to reduce scheduling over- head associated with regular transmissions such as voice over IP. Bandwidth adaptation/bandwidth part operation 5G/NR supports wide bandwidth operation, for example, in nmWave applications with car- rier bandwidth of up to 400 MHz. This wide bandwidth may not be required by the 20MHz 60KHz 40MHz 40MHz 15KHz 15KHz 10MHz 10MHz 15KHz 15KHz FIGURE 2-23 Bandwidth adaptation. Open Radio Access Network (O-RAN) Systems Architecture and Design ServingCellConfig BWP-Downlink BWP-DownlinkCommon bwp-ld genericParameters locationAndBandwidth initialDownlinkBWP (O) bwp-Common (O) pdcch-ConfigCommon (O) subcarrierSpacing downlinkBWP-ToReleaseList (O) bwp-Dedicated (O) pdsc