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PTRS – Reference signal

PTRS – Reference signal

Phase Tracking Reference Signal (PTRS) PT-RS use is mainly to estimate and minimize the effect of CPE on system performance. Due to the phase noise properties, PT-RS signal has a low density in the frequency domain and a high density in the time domain. PT-RS always occurs in combination with DM-RS and only when the…

PTRS – Reference signal

PTRS – Reference signal

Phase Tracking Reference Signal (PTRS) PT-RS use is mainly to estimate and minimize the effect of CPE on system performance. Due to the phase noise properties, PT-RS signal has a low density in the frequency domain and a high density in the time domain. PT-RS always occurs in combination with DM-RS and only when the…

Downlink control information

Downlink control information

DCI transports downlink control information for one or more cells with one RNTI. The following coding steps, can be identified: Information element multiplexing CRC attachment Channel coding Rate matching Category DCI Format Description DCI formats for scheduling of PUSCH Format 0_0 Fallback DCI. DCI format 0_0 is used for the scheduling of PUSCH in one…

What is V2X?

What is V2X?

V2X is a vehicular technology system that enables vehicles to communicate with the traffic and the environment around them, using short-range wireless signals. Intelligent transportation systems (ITSs) refer to services to improve traffic safety and increase efficiency. There are two types of V2X communication technology depending on the underlying technology being used: WLAN-based cellular-based IEEE first…

DFT-s-OFDM Signal Model

DFT-s-OFDM Signal Model

In the current NR specifications [2], [3], Discrete Fourier transform-spread orthogonal frequency-division multiplexing (DFT-s-OFDM) [14] is used for the uplink transmission, especially in coverage limited scenarios. This waveform is also referred to as single-carrier FDM waveform (SCFDM) in the literature. In 3GPP 5G NR, QAM modulation symbols with modulation order (4, 16, 64, 256) can…

Overview of L1 functions( Physical Layer)

Overview of L1 functions( Physical Layer)

The physical layer is expected to perform the following functions to provide the data transport service Error detection on the transport channel and indication to higher layers; FEC encoding/decoding of the transport channel; Hybrid ARQ soft-combining; Rate matching of the coded transport channel to physical channels; Mapping of the coded transport channel onto physical channels;…

Overview of L1 functions( Physical Layer)

Overview of L1 functions( Physical Layer)

The physical layer is expected to perform the following functions to provide the data transport service Error detection on the transport channel and indication to higher layers; FEC encoding/decoding of the transport channel; Hybrid ARQ soft-combining; Rate matching of the coded transport channel to physical channels; Mapping of the coded transport channel onto physical channels;…

Signaling radio bearers

Signaling radio bearers

Signaling Radio Bearers (SRBs) are defined as Radio Bearers (RBs) that are used only for the transmission of RRC and NAS messages. More specifically, the following SRBs are defined: SRB0 is for RRC messages using the CCCH logical channel. SRB1 is for RRC messages (which may include a piggybacked NAS message) as well as for…

QOS Model

QOS Model

The 5G QoS model is based on QoS Flows. The 5G QoS model supports both QoS Flows that require guaranteed flow bit rate (GBR QoS Flows) QoS Flows that do not require a guaranteed flow bit rate (Non-GBR QoS Flows). The 5G QoS model also supports Reflective QoS

What is 5G?

What is 5G?

5G has been introduced within the release 15 version of the 3GPP specifications.  5G has been specified based upon the requirements of the following use cases: Enhanced Mobile Broadband (eMBB) Ultra-Reliable and Low Latency Communications (URLLC) Massive Machine Type Communications (mMTC) • eMBB corresponds to a more or less straightforward evolution of the mobile broadband…