<style>
.title {
color: green;
font-weight:bold;
font-size: 20px;
}
.highlight {
color: red;
font-weight:bold;
border-bottom:2px red solid; padding-bottom:2px;
}
</style>
:::warning
# <center><i class="fa fa-book"></i> Introduction to 5G </center>
:::
*[5G]:5th generation wireless systems
*[backhaul]:後傳網路
*[Centralized RAN]:集中式無線接取網路
*[Fronthaul]:前傳網路
*[Antenna]: 天線
*[CUPS]: Control and User Plane Separation
###### tags: `study` `5G`
:::success
**🎯 Goals:**
- [x] - Understand the background knowledge of 5G
- [x] - [To know the characteristic of 5G](https://hackmd.io/D_DdrQjtRDCJ_v8_sB9a3Q?both#Module-2-the-characteristic-of-5G)
- [x] - <a href="#Module-3-the-overall-architecture-of-5G">To know the overall architecture of 5G</a>
- [x] - <a href="#Module-6-5G-NG-RAN-NextGen-RAN">To know the 5G NG-RAN Architecture</a>
- [x] - <a href="#Module-4-URLLCmMTCeMBB">Know the relationship between the URLLC/mMTC/eMBB Applications and Bandwidth/latency</a>
- [x] - <a href="#24-some-5G-Technology">Know some 5G Technology like Small Cell, Massive MIMO</a>
- [x] - <a href="#Module-5-SAStandalone-Non-SA">Know the deployment modes of SA(Standalone) Non-SA</a>
- [x] - <a href="#Module-7-Summary">Summary</a>
- [x] - <a href="#Module-8-QampA">Questions & Answers</a>
:::
[toc]
# Module 1: the previous generations
## 1.1 The differences between the previous generations and 5G advantage?
5G is designed to <font class="highlight">connect virtually everyone and everything together including machines, objects, and devices.</font>
:::spoiler Each generation of history
| First generation <font class = "title">1G</font> | Second generation <font class = "title">2G</font> |
|:------------------------------------------------:|:--------------------------------------------------:|
| 1980s: 1G delivered analog voice. | Early 1990s: 2G introduced digital voice. |
|  |  |
| Third generation <font class = "title">3G</font> | Fourth generation <font class = "title">4G LTE</font> |
|:------------------------------------------------:|:------------------------------------------------------:|
| Early 2000s: 3G brought mobile data. | 2010s: 4G LTE ushered in the era of mobile broadband. |
|  |  |
| Fifth generation - <font class = "title">5G</font> |
|:--------------------------------------------------:|
|  |
5G is a unified, more capable air interface. It has been designed with an extended capacity to enable next-generation user experiences, empower new deployment models and deliver new services.
:::
<font class="highlight">With high speeds, superior reliability and negligible latency</font>, 5G will expand the mobile ecosystem into new realms. 5G will impact every industry, making safer transportation, remote healthcare, precision agriculture, digitized logistics — and more — a reality.
## 1.2 Architecture for each generation
     
- As can be seen from the above figure, each base station must independently establish a connection with the surrounding base stations to exchange information. Compared with the two base stations, the situation ==becomes more complicated== .
If there are more, the number of connections will grow exponentially. This problem makes it difficult to coordinate the ==**interference**== between 4G base stations.
> point: 4G架構彼此基站干擾相當嚴重 (且依數量指數增加)
Advantages and disadvantages of 4G:
:::success
- **Advantages:** Latency reduction and deployment flexibility
:::
:::danger
- **Disadvantages:** Inefficiency of information exchange between stations
:::
      
- In the 5G era, the functions of the base station and core network have been reconstructed:
- **BBU** :arrow_right: **CU** and **DU**
- **RRU** and **Antenna** :arrow_right: **AAU**
<!-- 精簡為上面這段 -->
<!-- - the physical layer processing functions of the original BBU are downgraded to the RRU
- the RRU and the antenna are combined into an AAU
- the BBU is split into CU and DU
- CU also integrates a part of the function of sinking from the core network and exists as a centralized management node. -->
                   
- According to the real-time requirements of different protocol layers:
- **CU** :arrow_right: (not require high real-time) **PDCP and RLC**
- **DU** :arrow_right: (the physical high layer) **MAC, and RLC**
<!-- 精簡為上面這段 -->
<!--
The segmentation of CU and DU is carried out according to the real-time requirements of different protocol layers:
- the bottom layer in the original BBU is sunk into the AAU for processing
- the physical high layer, MAC, and RLC layers that require high real-time performance are placed in the DU for processing
- the PDCP and RLC layers that do not require high real-time performance are The RRC layer is placed in the CU for processing -->
## 1.3 4G 5G Comparasion
### 1.3.1 The upper part is a simple 4G network architecture
- Mobility Management Entity<font style="color:green">(MME)</font>: Be responsible for user mobility management.
> point: MME是LTE接入網絡的關鍵控制節點，管理用戶移動性
- Serving Gateway<font style="color:green">(SGW)</font>: Do session management and routing and forwarding of data.
> point: 屬於服務網關，負責用戶數據包的路由和轉發
- Packet Data Network Gateway<font style="color:green">(PGW)</font>: Responsible for connecting to external networks.
> point: 接入網絡發現和選擇功能
- Home Subscriber Server<font style="color:green">(HSS)</font>: Store information about users and their subscriptions for use as authentication authorization.
>point: 歸屬使用者伺服器，核心的使用者資料庫
>**SGW-C、PGW-C**: `控制介面`
>**SGW-U、PGW-U**: `使用者介面`
<!-- ### 1.3.2 The lower part of the picture, <font style="color:green">the green part</font> is Control Plane, and <font style="color:blue">the blue part</font> is User Plane. -->
### 1.3.2 Architecture shift between 4G and 5G:
| 4G | 5G |
| ------------ |:---------:|
| HSS | AUSF、UDM |
| MME | AMF、AUSF |
| SGW-C、PGW-C | SMF |
| SGW-U、PGW-U | UPF |
# Module 2: the characteristic of 5G
## 2.1 speed and bandwidth
- With a data rate of up to 10 Gbps
- [Cellular](https://zh.wikipedia.org/zh-tw/%E8%9C%82%E7%AA%9D%E7%BD%91%E7%BB%9C)
- mmW signals (heavy pathloss) but **multi-Gbps data** rates
<!-- 精簡成上面那段 -->
<!-- The most-discussed 5G feature is<font class="highlight"> increased speed and bandwidth</font>. With a data rate of up to 10 Gbps, 5G will bring a 10 times to 100 times improvement over the existing 4G LTE technology. Cellular is now a potential technology for branch office automation because WAN connections finally have enough bandwidth.
While mmW signals suffer from heavy pathloss in comparison with microwave signals, it is capable of enabling multi-Gbps data rates, albeit with smaller radii of 100-200m. -->
## 2.2 low latency
under 5 milliseconds, is the other key benefit for WAN usage.
## 2.3 low power consumption
from an infrastructure perspective, especially for IoT devices, the power savings could be significant.
## 2.4 5G Technology
### 2.4.1 Massive MIMO (multiple input, multiple output)
Improve 5G network coverage and system communication capabilities
It is technique refers to deploying a very **large** number of antennas at the <u>base station</u>, and thus, **improving** <u>energy</u> efficiency and <u>spectral</u> efficiency of wireless networks.
- Compared with 2 antennas, 4 antennas and **8** antennas of traditional equipment, the number of channels using Massive MIMO technology can reach 32 or **64**
- <u>Dimensional aspects of signal coverage.</u> From the movement in the **horizontal** direction before, to the movement in the **horizontal direction and the vertical** airspace, the radiation of the signal is an electromagnetic beam.
>**energy efficiency**: `能量效率`
>**spectral efficiency**: `頻譜效率`
:::success
- large number of antennas
- improving energy efficiency
- improving spectral efficiency
:::
### 2.4.2 Small cell
It is provides high data rate and good coverage with reduced transmit power by decreasing the distance between base station and user.
:::success
- high data rate
- good coverage
:::
### 2.4.3 Beamforming
When transmitting data, the router will first **detect the location of the connected device** and collect information about other transmission paths. Based on this content, the router can adjust and focus the signal direction to the device to achieve a **faster** and **more stable** signal connection.
Therefore, rather than broadcasting the signal in all directions, the targeted sending method can make the Wi-Fi signal transmission farther, and at the same time, it can also reduce the data transmission conflict between different data.
:::success
- Avoid signal interference
- Avoid signal degradation
:::
# Module 3: the overall architecture of 5G
## 3.1 Control Plane: CN (core Network)
<!-- The base station and related equipment of the mobile telecommunication system are called "cloud wireless access network", and are connected to the core network (CN) by backhaul. -->
<!--  -->
### 3.1.1 Details of each block
:::spoiler **detail** (Less than the main direction of the laboratory)
- <font style="color:green">(NSSF)</font> Network Slice Selection Function : select the service AMF for the UE.
- <font style="color:green">(NEF)</font> Network Exposure Function :
Secure exposure of network services (voice, data connectivity, charging, subscriber data, etc.) towards 3rd party application over APIs
> point: Core Network's API for 第三方應用
- <font style="color:green">(NRF)</font> Network Repository Function :
registration and deregistration of network elements, so that each network element can discover each other and communicate through API.
> point: 負責網路元件的設定，註冊和註銷，透過API進行通信。
> 還看不懂的網站：[5G Core Part 5 — Network Repository Function (NRF)](https://derekcheung.medium.com/5g-core-part-5-network-repository-function-nrf-5dd65afc6f12)
- <font style="color:green">(PCF)</font> Policy Control Function :
a functional element for policy control decision and flows based charging control functionalities.
>point: 負責用戶的策略管控和實施。
- <font style="color:green">(AF)</font>Application Function : application influence on traffic routing
- <font style="color:green">(NSSAAF)</font> Network Slice-specific and SNPN Authentication and Authorization Function
- <font style="color:green">(AUSF)</font> Authentication Server Function :
provides a network service that applications use to authenticate the credentials, usually account names and passwords, of their users.
>point: 認證授權功能，類似4G中的MME中的認證授權，負責對與連接該網路的3GPP系統或非3GPP系統的UE進行認證。
- <font style="color:green">(AMF)</font> Access and Mobility Management Function :
**is the most important function in the 5G core network**
receives all connection and session related information from the User Equipment (UE) (N1/N2) but is responsible only for handling connection and mobility management tasks.
>**UE (User Equipment)**: `用戶終端`
**SM (Session Management)**: `會話管理`
point: 負責UE的註冊、連接、訪問驗證授權、移動性和可達性管理，在UE和SMF之間提供SM消息的傳輸。
- <font style="color:green">(SMF)</font> Session Management Function :
The SMF is the control function that manages the user sessions including establishment, modification and release of sessions, and it can allocate IP addresses for IP PDU sessions.
> point: 管理會話建立，修改和釋放。根據自身配置或和PCF交互來制定策略，做會話選擇;負責UE的IP分配管理，具配DHCP，ARP代理或IPv6鄰居請求代理的功能。
- <font style="color:green">(SCP)</font> Service Communication Proxy : a decentralized solution.
>point: 負責路由控制。
- <font style="color:green">(NSACF)</font> Network Slice Admission Control Function
:::
### 3.1.2 Open CN
  Using Network slicing, a physical core network is divided into multiple virtual core networks supporting different functions, and each virtual network operates independently.
## 3.2 User Plane (The main direction of the laboratory)
<!--  -->
:::spoiler **5G Protocol Stack** (User Plane)
:::
<br>
### 3.2.1 <font style="color:green">**UE**</font> (User Equipment)
### 3.2.2 <font style="color:green">**RAN**</font> (Radio Access Network)
- **Antenna**: electrical signals :arrow_right: radio waves.
- **RRU** (Remote Radio Unit)): digital information :arrow_right: signals (radio frequency).
- **BBU** (Baseband Unit): Responsible for processing digital signals.
- different types of RANs:
- **O-RAN** (open radio access network)
- Open Radio Access Network refers to a new paradigm of network architecture in which a mobile network is composed of hardware and software systems from multiple vendors operating through truly open and interoperable network interfaces.
- **C-RAN** (cloud or centralized radio access network)
- Move the BBU to the "cloud computer room" and centralize it, called Centralized RAN, and use Fronthaul to connect the remote wireless units and antennas on the outdoor roof, which can greatly reduce the indoor computer room of the base station and reduce costs.
- **GRAN** (GSM radio access network)
<!--  -->
<!-- The base station and related equipment of the mobile telecommunications system are called "cloud wireless access network", and then "backhaul" is connected to the core network (CN). -->
### 3.2.3 <font style="color:green">**UPF**</font> (User Plane Function):
represents the data plane evolution of a Control and User Plane Separation (CUPS) strategy
*[Encapsulation]: 封裝
*[Decapsulation]: 解封裝
*[corresponds]: 對應
*[forwarding]: 轉發
*[inspection]: 檢查
- **connect RAN and DN**
- Encapsulation and Decapsulation of GTP-U Protocol
- Packet routing and forwarding, packet inspection
- QoS corresponds to the processing of the client
- Collect user traffic usage reports
<!-- 類似SGW/PGW。回應SMF的請求 -->
>point: 連接外部網路與區域網路
### 3.2.4 <font style="color:green">**DN**</font> (Data Network):
It identifies Service Provider services, Internet access or 3rd party services.
>point: 外部資料網路(如電信商網路，Internet，或者第三方的服務)。
><font style="color:green">(PDU)</font> Packet Data Unit: `5G網路傳送的封包格式`
包含IP，Ethernet，和非結構化的三種資料類型
> PDU傳送的建立方式：當UE有業務需求的時候，由UE主動發起一個Session，建立在UE和數據網路(DN)間一條新的數據通道。
> Session: `UE使用一個IP位址跟DN進行訊息交換。`
> UE可以在同時間對同一個DN或者多個DN建立不同的PDU Session。
> 而多個PDU Session在通過不同的UPF時，每個PDU Session所對應的SMF可以不同。
<!-- ## 3.3 CRAN (Cloud RAN)
Move the BBU to the "cloud computer room" and centralize it, called Centralized RAN, and use Fronthaul to connect the remote wireless units and antennas on the outdoor roof, which can greatly reduce the indoor computer room of the base station and reduce costs.
## 3.4 O-RAN (Open Radio Access Network)
Open Radio Access Network refers to a new paradigm of network architecture in which a mobile network is composed of hardware and software systems from multiple vendors operating through truly open and interoperable network interfaces.
## 3.5 Open CN
Using Network slicing, a physical core network is divided into multiple virtual core networks supporting different functions, and each virtual network operates independently. -->
# Module 4: URLLC/mMTC/eMBB
The relationship between the URLLC/mMTC/eMBB Applications and Bandwidth/latency
<!--  -->
| abbr. | <font style="color:orange">URLLC</font> | <font style="color:royalblue">mMTC</font> | <font style="color:green">eMBB</font> |
| ------- |:----------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------- |:--------------------------------------------------------------------------------- |
| Name | Ultra-reliable and Low Latency Communications | Massive Machine Type Communications | Enhanced Mobile Broadband |
| Chinese | 超可靠度和低延遲通訊 | 大規模機器型通訊 | 增強型行動寬頻通訊 |
| APPL. | - Low Latency <br> - High Reliabbility <br> - High Availability <br> - Loction precision | - Emergy Optimization <br> - High Connection Density <br> - Low Complexity <br> Extended Coverage | - Extreme throughput <br> - Enhanced spectral rfficiency <br> - Extended coverage |
# Module 5: SA(Standalone) Non-SA
## 5.1 SA (Standalone)
To build a new 5G base station
:::success
- The core network uses 5G architecture, no longer depends on 4G
- The transmission rate is not limited
:::
## 5.2 Non-SA (Non-Standalone)
It is the coexistence of 4G and 5G base stations.
:::success
- Low cost of resources required in the initial stage
:::
:::danger
- The transmission rate is limited
:::
# Module 6: 5G NG-RAN (NextGen RAN)
- Architecture
- A gNB may consist of a gNB-CU (Central Unit) and one or more gNB-DUs (Distribution Unit).
- A gNB-CU and the gNB-DU units are connected with F1 logical interface.
- One gNB-DU is connected to only one gNB-CU.
- NG, Xn, and F1 are logical interfaces.
NG-RAN is a part of the 3GPP 5G system
responsible for providing Radio Access to 5G networks.
- gNB
provides 5G NR access to the users by providing NR control
- NG-eNB
provides LTE Radio access to the users or provides E-UTRA control
- General Principles for NG-RAN
• Logical separation of signaling and data transport networks.
• NG-RAN and 5GC functions are fully separated from transport functions.
• RRC connection mobility is fully controlled by the NG-RAN.
• The NG-RAN interfaces are defined along with the following principles:
1. The functional division across the interfaces have as few options as possible.
2. Interfaces are based on a logical model of the entity controlled through this interface.
3. One physical network element can implement multiple logical nodes.
All interfaces are those defined by the 3GPP standard.
----
>**Fronthaul**: `前傳網路`
>**backhaul**: `後傳網路`
>**gNB(Next. Generation Node )**: `3GPP 對於5G 基地台的稱呼`
>**5G NR**:`5G新空中介面(New Radio)`
# Module 7: Summary
Compared with the previous generations of technologies, 5G has a breakthrough change. All technologies are white-labeled, and all manufacturers can produce their own products. Finally, products from different manufacturers can be combined with unified specifications. This is also 5G is expected to have breakthroughs. key points of sexual development.
>Chinese：<br>5G相較前面幾代技術有著突破性的改變，將所有技術白牌化，開放所有廠商皆可自行生產，最後藉由統一規格可以將不同廠商的產品接合在一起，這也是5G被看好將有突破性發展的關鍵點。
# Module 8: Q&A:
## 8.1 Question 1
Please answer why the network operators need open ran, its pros and cons ?
:::success
- Open RAN will take 5G from promise to practice by lowering costs, speeding innovation and improving user experience.
- Base station hardware equipment is no longer arbitrarily raised by large companies, and can start R&D and manufacturing by itself, or begin to popularize at a more affordable price
:::
:::danger
- The development of O-RAN requires new costs to cultivate talents
:::
## 8.2 Question 2
Please simply answer relationship with RAN, Core Network and Data Network ?
- **RAN**
- It connects a single device to the rest of the network via a radio link
- **Core Network**
- It is a central conduit designed to transport network traffic at high speed.
- **Data Network**
- It identifies Service Provider services, Internet access or 3rd party services.
Sign in with Wallet
Connect another wallet