5G/NR

5G NR (New Radio) Technology

Several amazing things come to our mind when we hear about the words 5G NR, like Fast data speed, Mission critical communications, Massive Internet of Things, Low latency, Reduced battery power, Massive MIMO, Beam Management, autonomous driving and many more. Here we will discuss about all these new features of 5G NR technology in details.

Table of Contents:

3GPP Specifications related to 5G NR:

Similar to LTE, 3G and other technologies, 5G NR technology also has many 3GPP specifications. There are tons of websites and papers about this technology. Sometimes it becomes difficult for the reader to find the right specification for a particular topic of interest. To help the readers, here we have collected this information in below table. For more details, please refer this 3GPP website link: "https://www.3gpp.org/".

5G NR Specification No. Title and Link of Specification

TS 38.101-1 User Equipment (UE) radio transmission and reception; Part 1: Range 1 Standalone

TS 38.101-2 User Equipment (UE) radio transmission and reception; Part 2: Range 2 Standalone

TS 38.101-3 User Equipment (UE) radio transmission and reception; Part 3: Range 1 and Range 2 Interworking operation with other radios

TS 38.101-4 User Equipment (UE) radio transmission and reception; Part 4: Performance requirements

TS 38.104 Base Station (BS) radio transmission and reception

TS 38.133 Requirements for support of radio resource management

TS 38.141 Base Station (BS) conformance testing

TS 38.173 TDD operating band in Band n48

TS 38.201 NR- Physical layer; General description

TS 38.202 NR- Services provided by the physical layer

TS 38.211 Physical channels and modulation

TS 38.212 Multiplexing and channel coding

TS 38.213 Physical layer procedures for control

TS 38.214 Physical layer procedures for data

TS 38.215 Physical layer measurements

TS 38.304 User Equipment (UE) procedures in idle mode and in RRC Inactive state

TS 38.306 User Equipment (UE) radio access capabilities

TS 38.321 Medium Access Control (MAC) protocol specification

TS 38.322 Radio Link Control (RLC) protocol specification

TS 38.323 Packet Data Convergence Protocol (PDCP) specification

TS 38.331 Radio Resource Control (RRC); Protocol specification

TS 38.401 NG-RAN; Architecture description

TS 38.425 NR user plane protocol

TS 38.521-1 User Equipment (UE) conformance specification; Radio transmission and reception; Part 1: Range 1 standalone

TS 38.521-2 User Equipment (UE) conformance specification; Radio transmission and reception; Part 2: Range 2 standalone

TS 38.521-3 User Equipment (UE) conformance specification; Radio transmission and reception; Part 3: Range 1 and Range 2 Interworking operation with other radios

TS 38.716-02-00 NR inter-band Carrier Aggregation (CA) / Dual Connectivity (DC) Rel-16 for 2 bands Down Link (DL) / x bands Up Link (UL) (x=1,2)

TS 38.716-03-01 NR inter-band Carrier Aggregation (CA) / Dual Connectivity (DC) Rel-16 for 3 bands Down Link (DL) / 1 bands Up Link (UL)

TS 38.716-03-02 NR inter-band Carrier Aggregation (CA) / Dual Connectivity (DC) Rel-16 for 3 bands Down Link (DL) / 2 bands Up Link (UL)

TS 38.819 LTE Band 65 for NR (n65)

TS 38.840 Study on User Equipment (UE) power saving in NR

TS 38.873 Time Division Duplex (TDD) operating band in Band n48

TS 38.885 Study on NR Vehicle-to-Everything (V2X)

TS 38.887 TDD operating band in Band n259

TS 38.889 Study on NR-based access to unlicensed spectrum

5G NR Specification No.	Title and Link of Specification
TS 38.101-1	User Equipment (UE) radio transmission and reception; Part 1: Range 1 Standalone
TS 38.101-2	User Equipment (UE) radio transmission and reception; Part 2: Range 2 Standalone
TS 38.101-3	User Equipment (UE) radio transmission and reception; Part 3: Range 1 and Range 2 Interworking operation with other radios
TS 38.101-4	User Equipment (UE) radio transmission and reception; Part 4: Performance requirements
TS 38.104	Base Station (BS) radio transmission and reception
TS 38.133	Requirements for support of radio resource management
TS 38.141	Base Station (BS) conformance testing
TS 38.173	TDD operating band in Band n48
TS 38.201	NR- Physical layer; General description
TS 38.202	NR- Services provided by the physical layer
TS 38.211	Physical channels and modulation
TS 38.212	Multiplexing and channel coding
TS 38.213	Physical layer procedures for control
TS 38.214	Physical layer procedures for data
TS 38.215	Physical layer measurements
TS 38.304	User Equipment (UE) procedures in idle mode and in RRC Inactive state
TS 38.306	User Equipment (UE) radio access capabilities
TS 38.321	Medium Access Control (MAC) protocol specification
TS 38.322	Radio Link Control (RLC) protocol specification
TS 38.323	Packet Data Convergence Protocol (PDCP) specification
TS 38.331	Radio Resource Control (RRC); Protocol specification
TS 38.401	NG-RAN; Architecture description
TS 38.425	NR user plane protocol
TS 38.521-1	User Equipment (UE) conformance specification; Radio transmission and reception; Part 1: Range 1 standalone
TS 38.521-2	User Equipment (UE) conformance specification; Radio transmission and reception; Part 2: Range 2 standalone
TS 38.521-3	User Equipment (UE) conformance specification; Radio transmission and reception; Part 3: Range 1 and Range 2 Interworking operation with other radios
TS 38.716-02-00	NR inter-band Carrier Aggregation (CA) / Dual Connectivity (DC) Rel-16 for 2 bands Down Link (DL) / x bands Up Link (UL) (x=1,2)
TS 38.716-03-01	NR inter-band Carrier Aggregation (CA) / Dual Connectivity (DC) Rel-16 for 3 bands Down Link (DL) / 1 bands Up Link (UL)
TS 38.716-03-02	NR inter-band Carrier Aggregation (CA) / Dual Connectivity (DC) Rel-16 for 3 bands Down Link (DL) / 2 bands Up Link (UL)
TS 38.819	LTE Band 65 for NR (n65)
TS 38.840	Study on User Equipment (UE) power saving in NR
TS 38.873	Time Division Duplex (TDD) operating band in Band n48
TS 38.885	Study on NR Vehicle-to-Everything (V2X)
TS 38.887	TDD operating band in Band n259
TS 38.889	Study on NR-based access to unlicensed spectrum

Table: 3GPP Specifications for 5G NR [Reference: https://www.3gpp.org/]

5G NR Radio Interface Protocol Architecture:

The 5G NR radio interface contains the Layer 1, 2 and 3. The Layer 1 (Physical Layer) specifications are defined in TS 38.200 series and 38.300 series describes the specification about Layers 2 and 3.

Figure: 5G NR Radio interface protocol architecture

The 5G NR radio interface protocol architecture around three layers; Layer 1, 2 and 3 is shown in above figure [Reference: 3GPP TS 38.201 ]. The Layer 1 (physical layer - PHY) interfaces with Layer 2 (Medium Access Control- MAC) and Layer 3 (Radio Resource Control- RRC). The information between physical layer and MAC layer is transferred over radio interface via transport channels and from MAC to Radio Link Control via Logical channels as shown in the figure.

5G NR Documents Relationship:

Usually readers face difficulties in finding the right documents for different layer of radio interfaces. Below figure shows a brief summary and interconnection between the physical layer and higher layer documents [Reference: 3GPP TS 38.201].

Figure: Relationships among physical layer documents

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5G NR Basic Fundamentals:

Before going into details, let us briefly discuss about the basic fundamentals of 5G NR and their network deployment options.

5G Network Deployment Options:
There are multiple options 5G technology can be deployed. Based on the network infrastructure, they can be divided in two different categories as given below.

Standalone (SA) :

Non-standalone(NSA):

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Features/Specifications Comparison Between 4G LTE and 5G NR ( 5g nr vs lte):

Here is the comparison between LTE and NR features/specifications for a quick view.

5G Performance requirements for high data rates and traffic densities:
The performance requirements for high data rates and traffic densities are defined by 3GPP in 3GPP TS 22.261 as given in the following table.

Scenario Experienced data rate (DL) Experienced data rate (UL) Area traffic capacity (DL) Area traffic capacity (UL) Overall user density

Urban 50 Mbps 25 Mbps 100 Gbps/KM² 50 Gbps/KM² 10,000 KM²

Rural 50 Mbps 25 Mbps 1 Gbps/KM² 500 Gbps/KM² 100 KM²

Indoor Hotspot 1 Gbps 500 Mbps 15 Tbps/KM² 2 Tbps/KM² 250,000 KM²

Dense Urban 300 Mbps 50 Mbps 750 Gbps/KM² 125 Gbps/KM² 25,000 KM²

High Speed Vehicle 50 Mbps 25 Mbps 100 Gbps/KM² 50 Gbps/KM² 4000 KM²

Scenario	Experienced data rate (DL)	Experienced data rate (UL)	Area traffic capacity (DL)	Area traffic capacity (UL)	Overall user density
Urban	50 Mbps	25 Mbps	100 Gbps/KM²	50 Gbps/KM²	10,000 KM²
Rural	50 Mbps	25 Mbps	1 Gbps/KM²	500 Gbps/KM²	100 KM²
Indoor Hotspot	1 Gbps	500 Mbps	15 Tbps/KM²	2 Tbps/KM²	250,000 KM²
Dense Urban	300 Mbps	50 Mbps	750 Gbps/KM²	125 Gbps/KM²	25,000 KM²
High Speed Vehicle	50 Mbps	25 Mbps	100 Gbps/KM²	50 Gbps/KM²	4000 KM²

Table: Performance requirements for high data rates and traffic densities

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Key Features of 5G NR Technology:

There are many new features available in 5G which make it more popular and attractive technology in the current time. Some of the key features are given below.

Frequency Band Support:

click here

5G supports wider bandwidth (BW) per component carrier. In FR1 range, it supports upto 100MHz BW, and in FR2, it supports upto 400MHz BW, where as LTE supports a maximun of 20MHz BW per component carrier.

Self Contend Slot Structure:

Low Latency and High Reliability:

Scalable Numerology :

Click here

Scalable Numerology

Forward Compatibility :

self contained

self confined

Advanced Channel Coding schemes:

LDPC

Polar codes

LTE NR Dual Connectivity:

EN-DC section

Support of Dynamic TDD:

New RRC Inactive State Support :

5G NR RRC States

Dynamic Spectrum Sharing:

Reduced Power Consumption :

Enhanced Multiple Antenna Techniques :

Other Improvements :

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5G NR Frequency Ranges and Operating Bands:

The Frequency ranges and operating bands given in this section are based on the operating bands and channel bandwidths defined in release-16 of 3GPP spec 38.104. New operating bands and channel bandwidths may be defined in future releases based on the new developments in this area.

5G NR Frequency Ranges:

NR Range Category Corresponding Frequency Range

FR1 410 MHz – 7125 MHz

FR2 24250 MHz – 52600 MHz

NR Range Category	Corresponding Frequency Range
FR1	410 MHz – 7125 MHz
FR2	24250 MHz – 52600 MHz

Table: 5G NR Frequency Ranges [Reference: 3GPP 38.104]

5G NR Operating Bands:

5G NR Operating Band Uplink Operating Band
F_UL,Low – F_UL,High Downlink Operating Band
F_DL,Low – F_DL,High Duplex Mode

n1 1920 MHz – 1980 MHz 2110 MHz – 2170 MHz FDD

n2 1850 MHz – 1910 MHz 1930 MHz – 1990 MHz FDD

n3 1710 MHz – 1785 MHz 1805 MHz – 1880 MHz FDD

n5 824 MHz – 849 MHz 869 MHz – 894 MHz FDD

n7 2500 MHz – 2570 MHz 2620 MHz – 2690 MHz FDD

n8 880 MHz – 915 MHz 925 MHz – 960 MHz FDD

n12 699 MHz – 716 MHz 729 MHz – 746 MHz FDD

n14 788 MHz – 798 MHz 758 MHz – 768 MHz FDD

n18 815 MHz – 830 MHz 860 MHz – 875 MHz FDD

n20 832 MHz – 862 MHz 791 MHz – 821 MHz FDD

n25 1850 MHz – 1915 MHz 1930 MHz – 1995 MHz FDD

n26 814 MHz – 849 MHz 859 MHz – 894 MHz FDD

n28 703 MHz – 748 MHz 758 MHz – 803 MHz FDD

n29 N/A 717 MHz – 728 MHz SDL

n30 2305 MHz – 2315 MHz 2350 MHz – 2360 MHz FDD

n34 2010 MHz – 2025 MHz 2010 MHz – 2025 MHz TDD

n38 2570 MHz – 2620 MHz 2570 MHz – 2620 MHz TDD

n39 1880 MHz – 1920 MHz 1880 MHz – 1920 MHz TDD

n40 2300 MHz – 2400 MHz 2300 MHz – 2400 MHz TDD

n41 2496 MHz – 2690 MHz 2496 MHz – 2690 MHz TDD

n48 3550 MHz – 3700 MHz 3550 MHz – 3700 MHz TDD

n50 1432 MHz – 1517 MHz 1432 MHz – 1517 MHz TDD

n51 1427 MHz – 1432 MHz 1427 MHz – 1432 MHz TDD

n53 2483.5 MHz –2495 MHz 2483.5 MHz–2495 MHz TDD

n65 1920 MHz – 2010 MHz 2110 MHz – 2200 MHz FDD

n66 1710 MHz – 1780 MHz 2110 MHz – 2200 MHz FDD

n70 1695 MHz – 1710 MHz 1995 MHz – 2020 MHz FDD

n71 663 MHz – 698 MHz 617 MHz – 652 MHz FDD

n74 1427 MHz – 1470 MHz 1475 MHz – 1518 MHz FDD

n75 N/A 1432 MHz – 1517 MHz SDL

n76 N/A 1427 MHz – 1432 MHz SDL

n77 3300 MHz – 4200 MHz 3300 MHz – 4200 MHz TDD

n78 3300 MHz – 3800 MHz 3300 MHz – 3800 MHz TDD

n79 4400 MHz – 5000 MHz 4400 MHz – 5000 MHz TDD

n80 1710 MHz – 1785 MHz N/A SUL

n81 880 MHz – 915 MHz N/A SUL

n82 832 MHz – 862 MHz N/A SUL

n83 703 MHz – 748 MHz N/A SUL

n84 1920 MHz – 1980 MHz N/A SUL

n86 1710 MHz – 1780 MHz N/A SUL

n89 824 MHz – 849 MHz N/A SUL

n90 2496 MHz – 2690 MHz 2496 MHz – 2690 MHz TDD

n91 832 MHz – 862 MHz 1427 MHz – 1432 MHz FDD**

n92 832 MHz – 862 MHz 1432 MHz – 1517 MHz FDD**

n93 880 MHz – 915 MHz 1427 MHz – 1432 MHz FDD**

n94 880 MHz – 915 MHz 1432 MHz – 1517 MHz FDD**

n95* 2010 MHz – 2025 MHz N/A SUL

Note: * The band n95 is applicable in China only.
** Variable duplex operation not enabled by the network.

5G NR Operating Band	Uplink Operating Band F_UL,Low – F_UL,High	Downlink Operating Band F_DL,Low – F_DL,High	Duplex Mode
n1	1920 MHz – 1980 MHz	2110 MHz – 2170 MHz	FDD
n2	1850 MHz – 1910 MHz	1930 MHz – 1990 MHz	FDD
n3	1710 MHz – 1785 MHz	1805 MHz – 1880 MHz	FDD
n5	824 MHz – 849 MHz	869 MHz – 894 MHz	FDD
n7	2500 MHz – 2570 MHz	2620 MHz – 2690 MHz	FDD
n8	880 MHz – 915 MHz	925 MHz – 960 MHz	FDD
n12	699 MHz – 716 MHz	729 MHz – 746 MHz	FDD
n14	788 MHz – 798 MHz	758 MHz – 768 MHz	FDD
n18	815 MHz – 830 MHz	860 MHz – 875 MHz	FDD
n20	832 MHz – 862 MHz	791 MHz – 821 MHz	FDD
n25	1850 MHz – 1915 MHz	1930 MHz – 1995 MHz	FDD
n26	814 MHz – 849 MHz	859 MHz – 894 MHz	FDD
n28	703 MHz – 748 MHz	758 MHz – 803 MHz	FDD
n29	N/A	717 MHz – 728 MHz	SDL
n30	2305 MHz – 2315 MHz	2350 MHz – 2360 MHz	FDD
n34	2010 MHz – 2025 MHz	2010 MHz – 2025 MHz	TDD
n38	2570 MHz – 2620 MHz	2570 MHz – 2620 MHz	TDD
n39	1880 MHz – 1920 MHz	1880 MHz – 1920 MHz	TDD
n40	2300 MHz – 2400 MHz	2300 MHz – 2400 MHz	TDD
n41	2496 MHz – 2690 MHz	2496 MHz – 2690 MHz	TDD
n48	3550 MHz – 3700 MHz	3550 MHz – 3700 MHz	TDD
n50	1432 MHz – 1517 MHz	1432 MHz – 1517 MHz	TDD
n51	1427 MHz – 1432 MHz	1427 MHz – 1432 MHz	TDD
n53	2483.5 MHz –2495 MHz	2483.5 MHz–2495 MHz	TDD
n65	1920 MHz – 2010 MHz	2110 MHz – 2200 MHz	FDD
n66	1710 MHz – 1780 MHz	2110 MHz – 2200 MHz	FDD
n70	1695 MHz – 1710 MHz	1995 MHz – 2020 MHz	FDD
n71	663 MHz – 698 MHz	617 MHz – 652 MHz	FDD
n74	1427 MHz – 1470 MHz	1475 MHz – 1518 MHz	FDD
n75	N/A	1432 MHz – 1517 MHz	SDL
n76	N/A	1427 MHz – 1432 MHz	SDL
n77	3300 MHz – 4200 MHz	3300 MHz – 4200 MHz	TDD
n78	3300 MHz – 3800 MHz	3300 MHz – 3800 MHz	TDD
n79	4400 MHz – 5000 MHz	4400 MHz – 5000 MHz	TDD
n80	1710 MHz – 1785 MHz	N/A	SUL
n81	880 MHz – 915 MHz	N/A	SUL
n82	832 MHz – 862 MHz	N/A	SUL
n83	703 MHz – 748 MHz	N/A	SUL
n84	1920 MHz – 1980 MHz	N/A	SUL
n86	1710 MHz – 1780 MHz	N/A	SUL
n89	824 MHz – 849 MHz	N/A	SUL
n90	2496 MHz – 2690 MHz	2496 MHz – 2690 MHz	TDD
n91	832 MHz – 862 MHz	1427 MHz – 1432 MHz	FDD**
n92	832 MHz – 862 MHz	1432 MHz – 1517 MHz	FDD**
n93	880 MHz – 915 MHz	1427 MHz – 1432 MHz	FDD**
n94	880 MHz – 915 MHz	1432 MHz – 1517 MHz	FDD**
n95*	2010 MHz – 2025 MHz	N/A	SUL
Note:	* The band n95 is applicable in China only. ** Variable duplex operation not enabled by the network.

Table: 5G NR operating bands in FR1 [Reference: 3GPP 38.104]

Operating Band of 5G NR Uplink and Downlink Operating Band
F_UL,Low – F_UL,High
F_DL,Low – F_DL,High Duplex Mode

n257 26500 MHz – 29500 MHz TDD

n258 24250 MHz – 27500 MHz TDD

n260 37000 MHz – 40000 MHz TDD

n261 27500 MHz – 28350 MHz TDD

Operating Band of 5G NR	Uplink and Downlink Operating Band F_UL,Low – F_UL,High F_DL,Low – F_DL,High	Duplex Mode
n257	26500 MHz – 29500 MHz	TDD
n258	24250 MHz – 27500 MHz	TDD
n260	37000 MHz – 40000 MHz	TDD
n261	27500 MHz – 28350 MHz	TDD

Table: 5G NR operating bands in FR2 [Reference: 3GPP 38.104]

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NR Scalable/Flexible Numerologies:

5G NR is planned to support many many new features/applications such as extreme data download speeds, very low latency applications like remote medical surgery, ultra-low power devices, massive internet of things and so on. NR Scalable/Flexible Numerologies plays a crucial role to support these new features. Below are few key points of the scalable numerology.

Scalable Subcarrier Spacing:

^μ

Number of Slots in NR:

^μ

click here

Numerology
[ μ ] Subcarrier Spacing:
Δf=2^μx15 KHz Number of slots
per subframe Slot Length =1 ms/2^μ

0 15 KHz 1 1 ms

1 30 KHz 2 500 μs

2 60 KHz 4 250 μs

3 120 KHz 8 125 μs

Numerology [ μ ]	Subcarrier Spacing: Δf=2^μx15 KHz	Number of slots per subframe	Slot Length =1 ms/2^μ
0	15 KHz	1	1 ms
1	30 KHz	2	500 μs
2	60 KHz	4	250 μs
3	120 KHz	8	125 μs

Table: Values of Subcarrier spacing and Number of slots for a given numerology

Introduction of Mini-slots:

Dynamic DL and UL slots configuration

Concept of Bandwidth Parts:

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5G NR Frame/Subframe/Slot Structures:

Before going into details of the frame structure, let us look at the values of some basic parameters related to frames and subframes as defined in 3GPP TS 38.211 document. First, the size of various fields in the time domain is expressed in time units

T

_c = 1/(Δf_max.N_f) where Δf_max = 480 KHz & N_f=4096 . The constant k=T_s/T_c=64 where

T

_s = 1/(Δf_ref.N_f,ref), Δf_ref = 15 KHz and N_f,ref=2048 .
The duration of downlink or uplink NR Frame is 10 ms long and it is calculated as T_f=(Δf_max.N_f/100).T_c. One frame consists of 10 Subframes of T_sf=(Δf_max.N_f/1000).T_c= 1 ms duration. Each frame is further divided into two equal sized half-frames 0 and 1. Half-frame 0 comprises subframes 0-4 and Half-frame 1 comprises subframes 5-9.

Figure: 5G NR Frame and Subframe Structure
Below figure shows the timing relation between Uplink and Downlink frames. UE sends Uplink frame before downlink frame with an advance time T_TA = (N_TA + N_TA,offset).T_c, where N_TA and N_TA,offset parameters are provided to the UE in the message n-TimingAdvanceOffset for the serving cell as given in 3GPP TS 38.213 document.

Figure: Downlink and Uplink timing relation
Slots and OFDM symbols: For a given subcarrier spacing configuration [μ], slots are numbered as n^μ_s ∈ {0, ...., N_slot^subframe,μ - 1} in increasing order within a subframe and n^μ_s,f ∈ {0, ...., N_slot^frame,μ - 1} within a frame. In one slot, there are N_slot^frame,μ consecutive OFDM symbols depending on the cyclic prefix values as given in below table. The start of a subframe is aligned in time with the start of OFDM symbol in the same subframe.

Numerology
[ μ ] N_symb^slot N_slot^frame,μ N_slot^subframe,μ Cyclic Prefix

0 14 10 1 Normal

1 14 for Normal CP,
12 for Extended CP 20 2 Normal,
Extended

2 14 40 4 Normal

3 14 80 8 Normal

4 14 160 16 Normal

Numerology [ μ ]	N_symb^slot	N_slot^frame,μ	N_slot^subframe,μ	Cyclic Prefix
0	14	10	1	Normal
1	14 for Normal CP, 12 for Extended CP	20	2	Normal, Extended
2	14	40	4	Normal
3	14	80	8	Normal
4	14	160	16	Normal

Table: Number of OFDM symbols per slot, slots per frame, and slots per subframe for normal and extended cyclic prefix
OFDM symbols in a slot can be categorized as 'downlink', 'flexible', or 'uplink' symbols. A UE which does not support full-duplex communication, is not expected to transmit in the uplink (or downlink) earlier than N_Rx-TxTc (or N_Tx-RxTc) after the end of the last received downlink (or transmitted uplink) symbol in the same cell where N_Rx-TxTc and N_Tx-RxTc are given in below tables [Ref: 3GPP TS 38.211]. The numerology parameter μ and the cyclic prefix for a bandwidth part are obtained from the higher-layer parameter subcarrierSpacing and cyclicPrefix, respectively.

Transition time Frequency Range FR1 Frequency Range FR2

N_Tx-Rx 25600 13792

N_Rx-Tx 25600 13792

Transition time	Frequency Range FR1	Frequency Range FR2
N_Tx-Rx	25600	13792
N_Rx-Tx	25600	13792

Table: Transition time N_Rx-Tx and N_Tx-Rx

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5G NR Physical Resources: Resource Element/Block/Grid Structures:

In case of 5G NR, Resource Element, Resource Block and Resource Grid are also defined similar to that of LTE. Before going into their details, let us first have a look at NR resource grid structure.
NR Resource Grid (RG): Overview of the NR Resource Grid is given in below grid diagram. At the first look, it seems to be very similar to the LTE resource grid, but for NR, the actual physical dimension will be changed based on the selected carrier and numerology parameter (μ).

For a given numerology and carrier, the size of the RG (number of subcarriers and OFDM symbols sets for DL or UL) and starting point at a common resource block are provided by higher-layer signalling. The carrier bandwidth is given by parameter carrierBandwidth and the starting position of the grid is given by parameter offsetToCarrier in the SCS-SpecificCarrier IE. The frequency location of a subcarrier is same as the center frequency of that carrier. The higher-layer parameter txDirectCurrentLocation in the SCS-SpecificCarrier IE gives the location of the transmitter DC subcarrier in downlink side and txDirectCurrentLocation in the UplinkTxDirectCurrentBWP IE providest the location of transmitter DC subcarrier in uplink side.
Antenna Port: According to 3GPP TS 38.211-4.4.1, "An antenna port is defined such that the channel over which a symbol on the antenna port is conveyed can be inferred from the channel over which another symbol on the same antenna port is conveyed ". In other words, the shared or control channel data which is conveyed over an antenna port can be inferred from the channel over which reference symbols (DM-RS) if they are conveyed over same antenna port, resource, slot and same Physical resource block. Below is the summary of the antenna ports defined in 3GPP TS 38.211.

Antenna Ports Uplink Channel/ Signal

Antenna ports starting with 0 For DMRS for PUSCH

Antenna ports starting with 1000 For SRS, PUSCH

Antenna ports starting with 2000 For PUCCH

Antenna port 4000 For PRACH

Antenna Ports	Uplink Channel/ Signal
Antenna ports starting with 0	For DMRS for PUSCH
Antenna ports starting with 1000	For SRS, PUSCH
Antenna ports starting with 2000	For PUCCH
Antenna port 4000	For PRACH

Table: NR Antenna ports for Uplink Channels/Signals

Antenna Ports Downlink Channel/ Signal

Antenna ports starting with 1000 For PDSCH

Antenna ports starting with 2000 For PDCCH

Antenna ports starting with 3000 For CSI Reference Signal

Antenna ports starting with 4000 For SS/PBCH block transmission

Antenna Ports	Downlink Channel/ Signal
Antenna ports starting with 1000	For PDSCH
Antenna ports starting with 2000	For PDCCH
Antenna ports starting with 3000	For CSI Reference Signal
Antenna ports starting with 4000	For SS/PBCH block transmission

Table: NR Antenna ports for Downlink Channels/Signals

Resource Element (RE): Similar to LTE, Resource Element in NR is defined as the smallest physical resource, which consists of one subcarrier in time domain and corresponding one OFDM symbol in frequency domain. As shown in above Resource Grid diagram, RE is the smallest element represented by (k, l)^th position in the above grid.
Resource Block (RB): Similar to LTE, RB in NR is defined as the block of 12 sub-carriers. More details on the way.
Unused Resource Block (URB): All the resource blocks in a channel bandwidth are not necessarily used for transmission. Some of the blocks are needed for the guardbands at both the edges of RF carrier to meet the out-of-band emission requirements. More details on the way.
Maximum Bandwidth in NR: Maximum possible carrier bandwidth in NR is limited to 275 RBs for any SCS. More details on the way.
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EN-DC / 5G NR Dual Connectivity:

The EN-DC term stands for E-UTRA-NR (new radio) Dual Connectivity which was initially introduced in 3GPP Release 15. This feature allows a mobile device /User Equipment to communicate with 4G LTE and 5G NR base stations simultaneously via tight inter-working between two networks.
As discussed in the 5G NR Basic Fundamentals/ Network Deployment Options section, there are mainly two categories of 5G NR deployment - one is Standalone and other one is Non-Standalone. In this section, we will discuss more about the Non-standalone scenario needed for EN-DC (dual connectivity), it's functioning and requirements. In Non-standalone case, 5G radio access network will be deployed in inter-working with the existing LTE network. Let us first discuss about the need of this inter-working.
Need of Network Interworking: Let us think about the time when the 4G LTE network was initially evolved from 3G. At that time, 4G LTE cells were deployed with partial coverage. Seamless service was provided to the users through interworking of 4G LTE with 3G network using Core Network-level interworking solution. In this solution, 3G Core Network entity (Serving GPRS Support Node) directly interacts with the 4G LTE Core Network Entities e.g. MME and Serving Gateway.
4G-5G Interworking: There are two solutions for 4G LTE and 5G NR networks interworking: RAN-level interworking and CN-level interworking. For EN-DC connectivity, RAN-level interworking is necessary in Non-Standalone option, since 5G New Radio cannot be used without 4G LTE Radio. Below figure shows the RAN-level interworking of 4G LTE and 5G NR.

Figure: RAN-level interworking of 4G LTE and 5G NR for EN-DC

Call Establishment in EN-DC using RAN level internetworking: Here are basic steps for the call flow of EN-DC.

UE sends an ATTACH request to the LTE network. Once the UE attached to the LTE network, it signals the network that it wants to simultaneously connect to 5G network also.
The Core netwrk check for the UE capability and authentication.
The LTE eNB then activates the bearer on the 5G NR network.
Finally, UE is connected to 4G LTE as well as 5G NR network simultaneously.

Connection Establishment and Mobility: In RAN-level interworking, RRC message for control protocol is transmitted over the 4G LTE radio interface, which means the connection establishment and mobility of the UE is mainly controlled by the LTE eNB.
User Data Traffic: User data can be transmitted simultaneously over LTE eNB and 5G NR gNB (PDCP aggregation). Even though the user data is mostly transmitted over 5G NR, LTE radio interface always stays connected for connection and mobility management since LTE network provides larger coverage than 5G NR.
Upgrade Needed: 4G LTE and 5G NR interworking can be achieved by upgrading the existing LTE eNB and using them with the new 5G Core network. Upgrade in LTE eNB is done at EPC (Evolved Packet Core) level by increasing the gateway capacity in EPC. The new 5G NR features e.g. network slicing can be supported using 5G core.

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5G NR RRC States:

Similar to the legacy technologies (3G, LTE etc.), in 5G NR also, a UE can move to different RRC states to optimize the battery consumption and other network resources. In 5G NR, a new RRC state is added, which is discussed below in more details.
5G NR RRC Inactive State: In the legacy (3G or LTE), once UE is attached to the network, it can stay in RRC Idle or RRC connected state based on the user data activities. These two states of the UE are not sufficient or optimized for the new ultra-low latency and low power applications. Hence, a new state of UE is defined in 5G NR, known as Inactive state. Let us briefly discuss about Inactive state, it's need and benefits.
What is Inactive State and it's need: Inactive state is the intermediate state of the UE between Idle and Connected state. The main idea of introducing the Inactive state of the UE is that it can return to the Connected state as quickly and efficiently as possible. Whenever there is no data activity, UE should quickly transition to the Inactive state in order to save it's battery power.
During the transition to Inactive state, UE as well as RAN store all the necessary information so that later on it can resume the connection whenever needed. This stored information needed to restore the secured connection, is a set of parameters such as UE identifier, security information and RAN Notification Area (RNA) within which UE can move around without notifying the network.
When there is a need of connection for data exchange, the Inactive UE can initiate the resume procedure. This involves the restoration of the previously store information and then resume the connection without extensive signal with the core network e.g. without having the re-establishment of the security procedure. In this case, the UE sends an RRC resume request to the network. This request message includes the UE identifier and a security token to verify authenticity of the request.
During the resume procedure (Inactive to Connected state), the number of RRC messages exchanged between the UE and the RAN reduce to three (compare to seven in case of Idle to Connected state). Reduced signaling is possible during this resume transition by sending only the delta parameters (only changed parameters). This option is not available in the legacy Idle to Connected state transition scenario.
In summary, this resume procedure from Inactive to Connected state is similar to the hibernate (sleep) state of a computer where user can pause a work and resume later without going through the long and tedious start-up procedure again. The need for the Inactive state of a UE arises with the growing field of the Machine-type Communication and other 5G applications such as Ultra-reliable low-latency communication (URLLC) and Enhanced Mobile Broadband (eMBB). The key benefits of introducing the Inactive state of the UE are the significantly reduced latency and optimized battery consumption of the UE.
5G NR RRC States and Transitions: As discussed above, 5G NR has three different RRC states: RRC IDLE, RRC INACTIVE and RRC CONNECTED as shown in the figure below.

UE transitioned between different states as summarized below.

After powering up, the UE first attaches to the network.
Once the UE is attached to the network, it goes to RRC connected state until it finishes the data exchange.
After finishing the data exchange, UE can move to RRC Idle state using RRC Release and can go back to RRC Connected state using RRC Connection Re-establishment messages (RRC CONNECTED <---> RRC IDLE).
Similarly, UE can move from RRC CONNECTED to RRC INACTIVE state and vice-versa using RRC Suspend and Resume messages (RRC CONNECTED <---> RRC INACTIVE).
From RRC INACTIVE state, UE can also move to RRC IDLE state, but it cannot go back to RRC INACTIVE state (RRC INACTIVE ---> RRC IDLE).

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5G NR Transmitter and Receiver Chains:

5G NR Transmitter and Receiver Chains are shown in below diagram. More detail will be discussed here soon.

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5G NR Downlink Channels and Signals:

5G NR Downlink Channels and Signals will be discussed here in detail.
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5G NR Uplink Channels and Signals:

5G NR Uplink Channels and Signals will be discussed here in detail.
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5G NR Control Resource Set (CORESET):

In 5G NR, a Control Resource Set (CORESET) is a set of physical resource blocks in frequency domain and OFDM symbols in time domain. The CORESET is located in Downlink Resource Grid and it carries the PDCCH (DCI). This is similar to the LTE control region. The LTE control region is generally fixed, but in NR, the set of OFDM symbols and RBs corresponding to the CORESET is configurable in terms of time, frequency and numerologies.
Figure below shows the LTE and NR control regions. Details coming soon.
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5G NR Beam Forming, Beam Scheduling and Beam Management:

5G NR Beam Forming, Beam Scheduling and Beam Management will be discussed here in detail.
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5G NR (New Radio) Technology

3GPP Specifications related to 5G NR:

5G NR Radio Interface Protocol Architecture:

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5G NR Basic Fundamentals:

Features/Specifications Comparison Between 4G LTE and 5G NR ( 5g nr vs lte):

Key Features of 5G NR Technology:

5G NR Frequency Ranges and Operating Bands:

5G NR Frequency Ranges:

5G NR Operating Bands:

NR Scalable/Flexible Numerologies:

5G NR Frame/Subframe/Slot Structures:

5G NR Physical Resources: Resource Element/Block/Grid Structures:

EN-DC / 5G NR Dual Connectivity:

5G NR RRC States:

5G NR Transmitter and Receiver Chains:

5G NR Downlink Channels and Signals:

5G NR Uplink Channels and Signals:

5G NR Control Resource Set (CORESET):

5G NR Beam Forming, Beam Scheduling and Beam Management:

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