1. What is 5G: 5G is referred as Fifth Generation of wireless technology in telecommunication industry. Previous generation of telecom standards are known as 1G,2G,3G and 4G.

One line statement for 5G is “High speed, Ultra reliable Low Latency network”

1G is referred as First generation telecom revolution and started around 1980s. It had analog voice only while 2G is known as Second generation  mobile technology and it started around 1990;s. It was better than1G and introduced digital voice i.e. better voice quality based on CDMA– Code Division Multiple Access).

3G is known as Third generation mobile technology and started during early 2000. This was really a game change in telecom industry and offered Voice and Data to customers.
WCDMA is technology background for 3G.

Next generation of telecom revolution is known as 4G… we are in 4G era today in most of the world!!. 4G is known as LTE ( Long Term Evolution). This enabled mobile broadband experience to the world.

So latest telecom technology is known as 5G which is designed with an extended capacity to enable next-generation user experiences, empower new deployment models and deliver new services. These services are never seen experience to world which includes connected car, smart factories and always connected feel.

5G will be both an evolution and a revolution. An evolution as mobile evolves to support a wide range of new use cases, and a revolution as the architecture concept is being predicted to completely transform to enable these new use cases.

• Provide fast, highly efficient network infrastructure
• Support more and more device connections
• Low latency, low power consumption
• Data rates that exceed 10 Gbps

5G includes the evolution of existing 4G networks that use technologies such as C-RAN and HetNet to increase capacity of existing networks with an affordable cost. But revolution for core architecture to fully use SDN/NFV and network ‘slicing’, the use of a new millimeter wave band air interface for higher capacity, and new architecture/signaling for extreme low latency.

2: 5G Standardization: 3GPP and ITU-R

Third Generation Partnership Project is known as 3GPP: This international body is a communications-focused organization made up of seven telecommunications standard development organizations called “organizational partners.” It is composed of supporting-member companies like the aforementioned companies. The organization is charged with formulating the 5G technical specifications, which ultimately become standards

ITU:   The International Telecommunications Union (ITU) This is other important standards formation body of 5G. The ITU is a Geneva-based United Nations agency focused on information and communication technologies. It coordinates the global sharing of radio spectrum. In 2015, the ITU identified three spectrum bands that will be used for 5G, and in 2016, it refined the criteria for the selection of 5G radio interface technologies.

IETF: The IETF is the standards body coming up with the key specifications for virtualization functions evolving IP protocols to support network virtualization.

3. 5G Frequency Bands:

3GPP has defend 5G frequency bands in to 2 parts known as FR1 and FR2.

FR1 and FR2 are the basic frequency band classifications for 5G-NR. These can be further classified into three bands –

• Frequency Division Duplex Bands (FDD)
• Time Division Duplex Bands (TDD)
• Supplementary Bands: Supplementary Downlink  Bands (SDL) & Supplementary Uplink Bands (SUL)

3. Millimeter wave.The millimeter wave is a band of radio spectrum between 30 GHz and 300 GHz and provides high-speed broadband connections to transfer data. This is the spectrum on which 5G operates. The millimeter wave spectrum travels at high frequencies in short, direct wavelengths, which is called line-of-sight travel. Due to the nature of millimeter wave, atmospheric changes — like increased humidity — and physical walls can affect performance and signal strength.

4. 5G NR: 5G NR stand for Fifth Generation New Radio. 5G New Radio (NR) is the global standard for a unified, more capable 5G wireless air interface. It will deliver significantly faster and more responsive mobile broadband experiences, and extend mobile technology to connect and redefine a multitude of new industries. And Qualcomm is the R&D engine at the center of the mobile ecosystem—making 5G NR a commercial reality.

5. OFDM.Orthogonal frequency-division multiplexing is a method of encoding data on multiple carrier frequencies: One data stream divides over separate channels with different frequencies. These separate channels help reduce and avoid interference. OFDM encoding is part of 5G’s framework, with channels between 100 MHz and 800 MHz.

OFDM techniques allow for densely packed sub-carriers without the need for guard bands and filters, increasing spectral efficiency and simplifying electronic design. OFDM is especially good in severe channel conditions where narrowband interference exists.

6. Dynamic Shared Spectrum (DSS) : Dynamic Spectrum Sharing (DSS) is a technology that allows the deployment of both 4G LTE and 5G NR in the same frequency band and dynamically allocates spectrum resources (by scheduler intelligently) between the two technologies based on user demand. DSS is seen as faster 5G roll out plan.

7. NSA and SA:

Since it is not possible to have 5G network everywhere initially.  In order to provide seemless connectivity existing4G network ( LTE/LTE-A) will be used. i.e 4G and 5G network will coexist.

The main difference between NSA (Non-Standalone) and SA (Standalone) is that NSA anchors the control signaling of 5G to the 4G base station, and the SA scheme is that the 5G base station is directly connected to the 5G core network, and the control signaling does not depend on the 4G network at al.

9. gNB or gNodeB: A node providing NR user plane and control plane protocol terminations towards the UE, connected via the NG interface to the 5GC.
The gNB is the logical 5G radio node, the equivalent of what was called NodeB in 3G-UMTS and eNodeB or eNB (i.e., evolved Node B) in 4G-LTE, is now called gNB.

10. MIMO & mMIMO: Multiple Input Multiple Output (MIMO) is an antenna technology is being in 4G& 5G.

MIMO is effectively a radio antenna technology as it uses multiple antennas at the transmitter and receiver to enable a variety of signal paths to carry the data, choosing separate paths for each antenna to enable multiple signal paths to be used.

MIMO allows multiple antennas to send and receive multiple spatial streams at the same time. MIMO makes antennas work smarter by enabling them to combine data streams arriving from different paths and at different times to effectively increase receiver signal-capturing power.

Massive multiple-input, multiple-output, or massive MIMO(mMIMO) is an extension of MIMO, which essentially groups together antennas at the transmitter and receiver to provide better throughput and better spectrum efficiency. Benefits of massive MIMO includes Increased Network Capacity, Improved Coverage  and User experience.

11.Beam Forming:

 Beamforming is a technique by which an array of antennas can be steered to transmit radio signals in a specific direction. … In this technique, each antenna element is fed separately with the signal to be transmitted. Phase and Amplitude of each Antenna is controlled & feedback of each communication channel is important in this function.

Some common terms used in Beamforming are:-

Beam switching: Switches between candidate beams to adapt to changing environment

Beam Steering: Changes direction of uplink beams to match the that of incoming beams from gNodeB

Beam Tracking: Distinguishes between beams arriving from gNodeB

12.Network Slicing:

Network slicing is a type of virtual networking architecture in the same family as software-defined networking (SDN) and network functions virtualization (NFV) — two closely related network virtualization technologies that are moving modern networks toward software-based automation. SDN and NFV allow far better network flexibility through the partitioning of network architectures into virtual elements. In essence, network slicing allows the creation of multiple virtual networks atop a shared physical infrastructure.

One of the primary benefits of network slicing is that network slices can be specifically configured to support certain use cases — whether that use case is the smart home, the Internet of Things (IoT) factory, the connected car, or the smart energy grid. Each use case receives a unique set of optimized resources and network topology—covering certain service level agreement-specified factors such as connectivity, speed, and capacity that all suit the needs of that application.

13. Software Defined Networking (SDN) is a way to manage networks that separates the control plane from the forwarding plane. It does so by using software to manage network functions through a centralized control point. SDN is a complementary approach to network functions virtualization (NFV) for network management. While they both manage networks, both rely on different methods. SD-WAN is an extension of SDN.

SDN offers a centralized view of the network, giving an SDN Controller the ability to act as the “brains” of the network. The SDN Controller relays information to switches and routers via southbound APIs, and to the applications with northbound APIs.

14. C-RAN – Centralized RAN A radio access network (RAN) architecture that separates baseband functions from antennas and remote radio heads (RRH) and pools baseband functions in centralized baseband units (BBU). A competing architecture to multi-access edge computing (MEC)

C-RAN architecture has three primary components — a centralized baseband unit (BBU) pool, remote radio unit (RRU) networks, and transport network or fronthaul:

• BBU pool — The BBU pool, located at a centralized site, functions as a cloudor a data center. Its multiple BBU nodes dynamically allocate resources to RRUs based on current network needs.
• RRU network — The wireless RRU network connects wireless devices similarly to access points or towers in traditional cellular networks.
• Fronthaul/transport network — Using optical fiber communication, cellular communication, or millimeter wave (mmWave) communication, the fronthaul is the connection layer between a BBU and a set of RRUs, providing high-bandwidth links to handle the requirements of multiple RRUs.

The C-RAN can lower the total cost of ownership (TCO) and it can improve network performance. It is particularly beneficial in low-latency network scenarios. The centralized cloud RAN architecture also provides the benefit of not requiring a rebuild of the transport network.

15. 5G Use cases:

• Fixed Wireless: One of the top 5G use cases will be fixed wireless access. Fixed wireless will provide Internet access to homes using wireless network technology rather than fixed lines. It will use 5G concepts such as millimeter wave (mmWave) spectrum and beamforming to bolster wireless broadband services.

• Enhanced Mobile Broadband: The 5G standard promises to usher in the next era of immersive and cloud-connected experiences with faster, more uniform data rates at lower latency and lower cost per bit. The 5G standard will take mobile computing performance to the next level with high-speed, always-on, always-connected internet links with real-time responsiveness. The goal is to reach up to 20 Gb/s peak throughput and 1 Gb/s throughput in high mobility. The need for high-speed internet with real-time responsiveness is seen with virtual reality (VR) and augmented reality (AR) experiences.
The 5G standard will take mobile computing performance to the next level with high-speed, always-on, always-connected internet links with real-time responsiveness. The goal is to reach up to 20 Gb/s peak throughput and 1 Gb/s throughput in high mobility. The need for high-speed internet with real-time responsiveness is seen with virtual reality (VR) and augmented reality (AR) experiences.
• Massive Machine-Type Communications: (MMTC) One of the most anticipated 5G use cases is the ability to seamlessly connect embedded sensors in virtually everything. The industry foresees huge numbers — as many as 20.4 billion — of potential IoT devices in service by 2020. Industrial IoT is one area where 5G will play a major role, enabling smart cities, asset tracking, smart utilities, agriculture, and security infrastructure (e.g. alarms or geofencing).
• Ultra-Reliable Low-Latency Communications: (URLLC)This category includes new services that will transform industries with ultra-reliable/available low-latency links, such as remote control of critical infrastructure, and (popularly) self-driving vehicles. The level of reliability and latency will be vital to smart-grid control, industrial automation, robotics, and drone control and coordination

16.Latency: Latency is measurement of delay between send and received signal. It is one of the very important features of 5G network. 5G networks have been targeting less 10millisecond latency & even better in future.

Use cases associated with low latency are:

• V2X (Vehicle-to-Everything) communication: V2V: (Vehicle-to-Vehicle), V2I (Vehicle-to-Infrastructure), autonomous, connected cars
• Immersive Virtual Reality Gaming (5G will bring VR to the masses)
• Remote surgical operations (aka telesurgery)
• Simultaneous translating.

There use cases will make 5G adoption popular and successful.

17. (X-haul). Xhaul refer to Crosshaul is new architecture that integrates fronthaul and backhaul in a single transport network to achieve overall reduction in capex and opex.

The 5G Crosshaul transport will use intelligent multiservice edge devices that combine heterogenous broadband access media (wireless or wired), flexible service delivery (enterprise or residential) and packet transmission services over optical fiber.

5G also imposes additional demands in terms of latency, jitter, scalability and connection bandwidth on the backhaul. This lead to modification of existing frontthaul and backhaul leading.

18. CPRI & e CPRI: Common Public Radio Interface (CPRI) is a specification for wireless communication networks that defines the key criteria for interfacing transport, connectivity and control communications between baseband units (BBUs) and remote radio units (RRUs), which are also called remote radio heads (RRHs). In other words

CPRI defines key interface specification between REC (Radio Equipment Control) and RE (Radio Equipment) of radio base stations used for cellular wireless networks. CPRI is popular standard for transporting baseband I/Q signals to the radio unit in traditional BS (Base Station). CPRI allows efficient and flexible I/Q data interface for various standards e.g. GSM, WCDMA, LTE etc.

eCPRI is published after CPRI. eCPRI standard defines specification which connects eREC and eRE via fronthaul transport network. It is used for 5G systems, LTE-Advanced and LTE-Advanced Pro.

eCPRI stands for Enhanced Common Public Radio Interface.
The basic idea is to divide functionalities of BS (Base Station) into two blocks viz. REC (Radio Equipment Control) and RE (Radio Equipment) and connect them via packet based fronthaul transport network such as Ethernet or IP. This is shown in the figure-1. Both REC and RE are usually connected using optical fiber link. REC and RE terms are used with CPRI where as same terms are renamed as eREC and eRE in eCPRI interface.

In comparison to CPRI interface, eCPRI decreases data rate requirements between eREC and eRE using flexible functional decomposition while maintaining complexity of eRE

19. Time-Sensitive Networking (TSN): TSN is a set of open standards specified by IEEE 802.1 . TSN standards are primarily for IEEE Std 802.3 Ethernet, which means they utilize all the benefits of standard Ethernet, such as flexibility, ubiquity and cost savings.

Time synchronization is a key component in all cellular networks. TSN is more relevant in 5G to meet industrial automation/ Industry 4.0 ultra-reliable low latency use cases and in fact part of 5G definition.

20. IoT- Internet of Things is a system consists of sensors/devices which “talk” to the cloud through some kind of connectivity. Once the data gets to the cloud, software processes it and then might decide to perform an action, such as sending an alert or automatically adjusting the sensors/devices without the need for the user.. As per 5G definition and expectation IoT will be one of the best use cases where more and more devices will be connected, monitored and controlled in high speed, ultra-reliable and low latency network-5G. Healthcare, Agriculture, Food processing , Food storage, Logistic, Smart Cities, Smart Homes are some of area where massive data will be generated and transferred. To handle such data 5G will play important role. 5G and IoT together will also help in bringing every item on the shelf to the internet by creating digital twins for them. If the number of hardware connected devices is expected to be in the billions, the potential for ordinary consumer products with digital twins to be a part of the new Internet of Things is considerably more

Author:  Madhukar Tripathi (Anritsu India Pvt Ltd)