What is semi persistent scheduling LTE?
The semi-persistent scheduling is a feature that significantly reduces control channel overhead for applications that require persistent radio resource allocations, such as VoIP. In LTE, HARQ RTT is 8 ms, which means retransmissions of resource blocks that have failed to be decoded can occur every 8 ms.
What is SPS in 5g?
Type of Downlink Scheduling One is called ‘Dynamic Scheduling’ and the other one SPS(Semi Persistent Scheduling’). Dynamic scheduling is the mechanism in which each and every PDSCH is scheduled by DCI(DCI 1_0 or DCI 1_1). SPS is the mechanism in which the PDSCH transmission is scheduled by RRC message.
What is scheduling request in LTE?
LTE Quick Reference Go Back To Index Home : www.sharetechnote.com. SR (Scheduling Request) SR is a special Physical Layer message for UE to ask Network to send UL Grant (DCI Format 0) so that UE can transmit PUSCH.
How does LTE scheduling work?
What is a LTE Scheduler ? Scheduling is a process through which eNodeB decides which UEs should be given resources (RBs), how much resource (RBs) should be given to send or receive data . In LTE, scheduling is done at per subframe basis i.e. every 1 mili second. The entity which is govern this is know as scheduler.
What is frequency selective scheduling in LTE?
Uplink frequency-selective scheduling (UL FSS) is important and applied in LTE that allocate the spectrum for PUSCH transmissions. Sounding UEs are mainly multiplexed in two different ways, either by means of code or frequency.
What is BSR in LTE?
BSR is a kind of MAC CE from UE to Network carrying the information on how much data is in UE buffer to be sent out.
What is Pdsch in 5G?
PDSCH (Physical Downlink Shared Channel) is the data-bearing channel in 5G-NR. For acquiring the channel quality, NR specifies a special type of cell-specific reference signal which can be configured for transmission on up-to 32 antenna ports. The CSI-RS resources are code, frequency and time division multiplexed.
What is RBG in 5G?
An RBG is a set of consecutive Virtual Resource Blocks (VRB). In type 0, non-interleaved VRB-to-PRB mapping is performed, meaning that VRBn is directly mapped to PRBn. The number of RBs within an RBG are derived based on the RRC parameter rbg-size configured by PDSCH-Config and the size of the bandwidth part.
How is semi persistent scheduling problem in LTE system?
The semi-persistent scheduling introduction. LTE system schedules the resource by the way of shared, although to get the maximum use of resource, but this way increases the cost on control signal. Thus, decreasing the control information is the unavoidable problem need to resolve.
Why is semi persistent scheduling important in VoIP?
The frequent arrival/transmission of VoIP packet means large control overhead for lower layers (L1/L2) in the radio protocol stack. To deal with this issue, semi persistent scheduling plays an important role. Scheduling is a mechanism where UE requests eNB for the resource allocation during each transmission time interval (TTI).
When to use semi persistent scheduling in TTI?
In case of semi persistent scheduling, eNB can assign predefined chunk of radio resources for VoIP users with interval of 20ms. Therefore, UE is not required to request resources each TTI, saving control plan overhead.
Which is an example of semi persistent scheduling?
The semi-persistent scheduling (SPS)–based resource allocation refers to a transmission mode in which the serving base station allocates at least a part of resources and transport formats to the UE semi-statically over a certain time interval consisting of a number of TTIs.