介紹 (Introduction) (p4) Translation (Introduction)

 行動蜂巢系統是一種分布於稱為「小區 (cells)」的土地區域上的無線系統。 A mobile cellular system is a wireless system distributed over land areas called cells.
o 小區共同提供覆蓋廣大的無線電信號範圍。 o Cells together provide radio coverage over a wide geographic area.
o 用戶可以在地理區域內移動，從一個小區切換到另一個小區。 o Users can move around this geographical area, transitioning from one cell to another.
 每個小區由「基地台 (Base Station, BS)」服務，基地台通常位於小區的中心位置。 Each cell is served by a Base Station (BS), usually located in the center of the cell.
 用戶被稱為「行動台 (Mobile Stations, MSs)」。 Users are referred to as Mobile Stations (MSs).
 小區的定義：由基地台覆蓋的區域，該區域內的無線電資源由該基地台控制。 A cell is defined as the area covered by a Base Station, wherein the radio communication resources used by the
o 小區內的行動台與對應的基地台連接並由其提供服務。 Mobile Stations (MSs) are controlled by the Base Station (BS).
總結重點 o MSs in a cell are connected to and served by the corresponding BS.
1. 行動蜂巢系統的結構： Key Points (Summary)
1. Structure of Mobile Cellular Systems:
o 小區 (cells) 是地理區域內的單位，提供無線電覆蓋。
o Cells are units of geographic areas providing radio coverage.
o 用戶 (MSs) 在小區之間移動，能夠保持服務連接。
o Users (MSs) move between cells while maintaining network connectivity.
2. 基地台 (Base Station, BS)：
2. Base Station (BS):
o 每個小區都有一個中心的基地台，負責該小區內的服務。 o Each cell is served by a central Base Station, responsible for communication within the cell.
3. 小區控制： 3. Cell Control:
o 小區內的所有資源管理及行動台的連接都由基地台負責。 o All resources and user connections in a cell are managed by the corresponding Base Station (BS).
相關概念 Related Concepts
1. 小區與基地台的對應關係： 1. Relationship Between Cells and Base Stations:
o 每個小區與一個基地台相對應，這確保了網路覆蓋和用戶移動性之間的銜接。 o Every cell corresponds to one Base Station. This ensures seamless connectivity and efficient user mobility.
2. 行動台 (MSs)： 2. Mobile Stations (MSs):
o 指用戶端設備，如手機、平板等，它們需要連接基地台才能使用網路。 o These refer to user devices like smartphones or tablets, which rely on Base Stations to access network
3. 切換 (Handover)： services.
o 當行動台從一個小區移動到另一個小區時，需要與新小區的基地台建立連接，這個過程叫做切換。 3. Handover (or Handoff):
範例解釋 o When an MS moves from one cell to another, it switches its connection to the new cell’s Base Station. This
1. 用戶移動的情境： process is known as a handover, ensuring uninterrupted communication.
Examples for Better Understanding
o 假設你在城市中從地鐵站 A 移動到地鐵站 B。 1. User Mobility Scenario:
o 在地鐵站 A，手機連接的是小區 A 的基地台。 o Imagine you are traveling in a city from subway station A to subway station B.
o 當你移動到地鐵站 B，手機會自動從小區 A 切換到小區 B 的基地台，確保你不會中斷通話或網路連接。 o At subway station A, your mobile device is connected to the Base Station of cell A.
2. 小區的覆蓋範圍： o As you move to subway station B, your device automatically switches to the Base Station of cell B. This
o 在城市區域，基地台通常安裝在建築物的高處，以提供更廣的信號覆蓋。 seamless transition ensures that your phone call or internet session remains active without interruption.
o 在郊區，基地台的數量較少，但每個基地台的覆蓋範圍更大。 2. Cell Coverage:
3. 實際應用： o In urban areas, Base Stations are often installed on rooftops to provide better coverage to a densely populated
o 假如你在進行直播，當你的車穿越多個小區，你的手機會不斷切換連接不同的基地台，直播不會中斷，這是蜂 area.
巢系統切換技術的貢獻。 o In rural areas, fewer Base Stations are deployed, but each Base Station covers a much larger area due to lower
population density.
3. Practical Application:
o If you are live-streaming while traveling, your phone will keep switching connections from one Base Station
to another as you pass through multiple cells. This capability, enabled by the cellular system, ensures your live
stream remains uninterrupted.

介紹 (Introduction)(p5) Translation (Introduction)

 在無線和行動系統中，電話號碼可以在跨地理區域移動的過程中保持不變。  In a wireless and mobile system, the telephone number is maintained across geographical areas while users
總結重點 are on the move.
移動保持連接： Key Points (Summary)
用戶在跨越地理區域（如從 Cincinnati 到 Washington, DC）的移動過程中，能夠保持相同 1. Maintaining Connectivity Across Cells:
話號碼與連接。 o Mobile users can travel across different geographic areas (e.g., from Cincinnati to Washington, DC) while
行動蜂巢系統的核心特性，支持用戶無縫切換小區而不會中斷通訊。 keeping the same phone number and network connection.
Cell) 與基地台 (Base Station)： o This feature of mobile cellular systems enables seamless handovers between cells without disrupting
是蜂巢系統的基本單位，每個小區由一個基地台服務。 communication.
2. Cells and Base Stations:
台負責小區內的所有通信連接，當用戶移動到另一個小區時，會切換到新小區的基地台（Handover）。
o Cells are the fundamental units of a cellular system, and each cell is served by a Base Station (BS).
：
o The Base Station manages all communications within the cell. When users move to a new cell, their connection
通常以六邊形排列，這是為了最大化覆蓋範圍並減少鄰近小區的干擾。
is handed over to the new Base Station (Handover).
相關概念 3. Cellular Structure:
1. 小區切換 (Handover)： o Cells are typically arranged in a hexagonal pattern to maximize coverage and minimize interference with
o 當用戶駕車從 Cincinnati 移動到 Washington, DC，他們的行動裝置會不 neighboring cells.
 斷切換連接不同小區的基地台。 Related Concepts
o 切換過程對用戶透明，通話或數據傳輸不會中斷。 1. Handover Process:
2. 地理覆蓋： o As a user drives from Cincinnati to Washington, DC, their mobile device continuously switches between Base
o 行動蜂巢系統的設計保證了即使用戶從一個地區移動到另一個地區，也可以保持網絡連接穩定。 Stations in different cells.
3. 電話號碼保持不變： o This handover process is seamless to the user, ensuring that ongoing calls or data transfers remain
o 行動蜂巢系統中，電話號碼與用戶的行動裝置綁定，而非特定小區，因此用戶在跨小區甚至城市移 uninterrupted.
動時，電話號碼保持不變。 2. Geographical Coverage:
範例解釋 o The design of mobile cellular systems ensures stable network connectivity even as users move between
1. 日常使用情境： different regions.
o 假設你在駕車旅行，從 Cincinnati 到 Washington, DC。途中你正在進行 3. Phone Number Consistency:
o In cellular systems, the phone number is tied to the user's device rather than a specific cell. This allows users
電話會議或使用網絡服務。
to move across cells or cities without changing their phone number.
o 當你穿越多個小區時，手機會自動切換到每個新小區的基地台。你不需要任何手動操作，通訊保持
Examples for Better Understanding
不中斷。 1. Daily Usage Scenario:
2. 實際應用場景： o Imagine you are driving from Cincinnati to Washington, DC, while on a phone call or using the internet.
o 當你搭乘高速列車移動時，手機需要迅速切換小區的連接來保持穩定的信號。 o As you pass through multiple cells, your phone automatically connects to the Base Station of each new cell.
o 蜂巢系統的優化確保了在高速移動下的穩定性和連續性。 This happens seamlessly without any interruption to your call or data session.
3. 蜂巢結構的設計： 2. Practical Applications:
o 六邊形小區排列方式可以減少覆蓋盲區，並為不同小區的基地台分配頻率以避免干擾。 o When traveling on a high-speed train, your phone needs to quickly switch between cells to maintain a strong
signal.
o The cellular system is optimized to ensure stability and continuity even at high speeds.
3. Design of the Cellular Structure:
o Hexagonal cell design minimizes coverage gaps and allocates frequencies efficiently to reduce interference
between neighboring cells.

介紹 (Introduction)(p6) Introduction
 無線資源管理 (Radio Resource Management, RRM)  Radio Resource Management (RRM)
o 一套機制，用於有效利用可用的無線頻譜資源和無線網絡基礎設施。 o A set of mechanisms aimed at efficiently utilizing available radio spectrum resources and the radio network
 RRM 涉及控制無線網絡的多種策略和算法，包括： infrastructure.
o 頻道分配 (Channel Allocation)：指分配頻譜資源。  RRM involves various strategies and algorithms to control the following:
o 接入控制 (Admission Control) o Channel Allocation: Assignment of spectrum resources.
o 切換條件 (Handoff Criteria) o Admission Control
o 功率控制 (Power Control) o Handoff Criteria
o 調變和錯誤編碼方案 (Modulation and Error Coding Schemes) o Power Control
o 波束成形 (Beamforming) o Modulation and Error Coding Schemes
總結重點 o BeamformingKey Points
1. 無線資源管理 (RRM) 的目的： 1. Purpose of RRM:
o 確保無線頻譜資源的高效利用。 o Ensure efficient use of radio spectrum resources.
o 同時保證無線網絡基礎設施的穩定運行。 o Maintain stable operation of the radio network infrastructure.
2. RRM 的關鍵控制策略： 2. Key Strategies in RRM:
o 頻道分配：為不同用戶或設備分配頻譜資源，確保避免干擾並最大化頻譜利用率。 o Channel Allocation: Assign spectrum resources to different users or devices to maximize spectrum utilization and
o 接入控制：確定哪些設備可以連接到網絡，以避免超載或資源分配失敗。 avoid interference.
o 切換條件：決定用戶在什麼情況下從一個小區切換到另一個小區，以保持穩定的連接。 o Admission Control: Determine which devices are allowed to connect to the network to prevent overload or resource
allocation failures.
o 功率控制：調整設備和基地台之間的信號發射功率，減少干擾並節省能量。 o Handoff Criteria: Decide under what conditions users should transition from one cell to another to maintain stable
o 調變與錯誤編碼：選擇適當的技術以提高數據傳輸的效率和可靠性。 connectivity.
o 波束成形：通過定向發送信號來增強特定方向的信號強度並降低其他方向的干擾。 o Power Control: Adjust the transmission power between devices and Base Stations to reduce interference and
相關概念 conserve energy.
1. 與前面內容的連結： o Modulation and Error Coding: Select appropriate techniques to improve data transmission efficiency and reliability.
o 小區 (Cell) 和 基地台 (Base Station) 的運行需要依賴 RRM 策略來管理資源分配和用戶連接。 o Beamforming: Enhance signal strength in specific directions while reducing interference in others by directing the
o 切換 (Handover) 是 RRM 中的重要部分，確保用戶跨小區移動時的無縫連接。 transmitted signal.
2. 核心專有名詞解釋： Related Concepts
o Beamforming (波束成形)：指通過調整天線信號的相位和幅度，將信號能量集中到某一方向。這在 5G 1. Connection to Previous Slides:
技術中尤為重要，可以提升信號質量和容量。 o Cells and Base Stations rely on RRM strategies to manage resource allocation and user connections.
o Power Control (功率控制)：避免基站之間的信號干擾，並確保連接穩定。 o Handoff is a critical part of RRM, ensuring seamless connectivity as users move between cells.
範例解釋 2. Core Terminology:
1. 頻道分配 (Channel Allocation)： o Beamforming: A technique that adjusts the phase and amplitude of antenna signals to concentrate energy in a
specific direction. This is crucial in 5G to improve signal quality and capacity.
 o 假設有多個用戶同時連接到一個基地台，RRM 會根據用戶的位置和需求，分配不同的頻道（例如不同的頻率）以避免干 o Power Control: Prevents interference between Base Stations and ensures stable connections.
擾。 Examples for Better Understanding
2. 切換條件 (Handoff Criteria)： 1. Channel Allocation:
o 用戶從小區 A 移動到小區 B 時，RRM 根據信號強度（例如接收功率是否低於一定閾值）決定是否觸發切換。 o Suppose multiple users are connected to a single Base Station. RRM allocates different channels (e.g., frequencies) to
3. 波束成形 (Beamforming)： users based on their location and needs to avoid interference.
o 在室內辦公環境中，RRM 通過波束成形增強特定方向的 Wi-Fi 信號，例如朝向會議室的信號增強，避免對其他空間 2. Handoff Criteria:
的干擾。 o When a user moves from Cell A to Cell B, RRM evaluates the signal strength (e.g., whether the received power is
below a certain threshold) to decide whether to trigger the handoff process.
3. Beamforming:
o In an office environment, RRM uses beamforming to strengthen Wi-Fi signals in a specific direction, such as toward a
meeting room, while minimizing interference to other areas.
細胞形狀（Cell Shape）(p8) Cell Shape
 理想情況下，由基地台（BS, Base Station）覆蓋的區域可以用圓形細胞來表示。  Ideally, the area covered by a Base Station (BS) can be represented by a circular cell.
總結： Summary:
這張投影片的主要觀念是，基地台覆蓋的理想範圍可以視為一個圓形的細胞，半徑 RRR 代表基地台的最大覆蓋距離。這 This slide illustrates the concept that the ideal coverage area of a base station is modeled as a circular cell. The
種理想模型用於描述基地台的服務區域，但實際情況可能因環境因素（如建築物、地形等）或干擾而有所不同。 radius RRR represents the maximum coverage distance of the base station. While this model is ideal for theoretical
purposes, real-world conditions such as environmental factors (e.g., buildings, terrain) and interference often lead to
deviations from this ideal shape.
相關重要觀念：
1. 基地台（Base Station, BS）：
o 是蜂巢式網路中的關鍵設備，負責與用戶設備（User Equipment, UE）進行通訊。 Key Concepts:
o 覆蓋範圍稱為細胞（Cell）。 1. Base Station (BS):
2. 圓形細胞模型的應用： o A critical component in cellular networks, responsible for communication with User Equipment (UE).
o 用於網路規劃以估計覆蓋範圍與容量。 o The coverage area of a base station is referred to as a "cell."
o 假設信號均勻向四周輻射，並忽略障礙物或干擾。 2. Application of Circular Cell Model:
3. 實際挑戰與改良模型： o Used in network planning to estimate coverage and capacity.
o 實際細胞形狀會受到地形、建築物遮擋及其他無線電信號干擾的影響，通常不是理想的圓形。 o Assumes that signals radiate uniformly in all directions, ignoring obstructions or interference.
o 改良模型包括蜂巢狀(hexagonal cell)，用於更準確地模擬細胞覆蓋與減少重疊。 3. Practical Challenges and Improved Models:
o The actual shape of a cell is often influenced by terrain, buildings, and radio signal interference, leading to non-ideal
shapes.
Example 幫助理解： o Improved models include hexagonal cells, which better represent cellular coverage and reduce overlap.
假設某基地台的覆蓋半徑 R 為 2 公里：
 理想情況：該基地台的服務範圍為一個半徑 2 公里的圓形，面積為 π×R2=π×22≈12.57
km2。 Example for Better Understanding:
 實際情況：由於城市中的建築物遮擋，覆蓋範圍可能被壓縮成不規則形狀，例如部分區域的覆蓋僅達 1 公里，而 Suppose a base station has a coverage radius RRR of 2 km:
在空曠地帶可能延伸至 2.5 公里。  Ideal Case: The service area of the base station is a circle with a radius of 2 km, and the area is
π×R2=π×22≈12.57 km2.
 Real-World Case: Due to building obstructions in an urban area, the coverage might shrink to 1 km in some
與前幾張的可能相關概念：
directions, while in open areas, it might extend up to 2.5 km.
 蜂巢狀網路規劃（Hexagonal Cell Planning）：實際無線通訊中，多個圓形細胞會導致
覆蓋重疊與干擾，因此常用蜂巢模型進行設計。
 頻率再利用（Frequency Reuse）：為了減少干擾與提高頻譜利用率，細胞之間會進行頻率分配 Possible Related Concepts from Previous Slides:
規劃，這通常依賴理想細胞模型進行分析。  Hexagonal Cell Planning: In real-world wireless communication, circular cells often lead to overlapping coverage
and interference, so hexagonal models are commonly used for network design.
 Frequency Reuse: To minimize interference and maximize spectrum efficiency, frequencies are allocated
strategically among cells, often analyzed using idealized cell models.

細胞形狀（Cell Shape）(p9) Cell Shape

 實際細胞的形狀由周圍區域的接收到的信號強度決定。  The actual shape of the cell is determined by the received signal strength in the surrounding area.
o 覆蓋範圍可能會有些扭曲。 o The coverage area may be a little distorted.
總結： Summary:
這張投影片的重點是，理想細胞(Ideal Cell)模型假設覆蓋範圍是完美的圓形，但在現實中，因為信號強度受到環境 This slide highlights that while the ideal cell (Ideal Cell) assumes a perfect circular coverage, the actual cell (Actual
影響(例如建築物、地形、干擾等)，實際細胞（Actual Cell）的覆蓋範圍通常並非完美的圓形，可能呈現不規則 Cell) shape is often irregular due to environmental factors. These factors include signal strength variations caused by
形狀。 obstacles like buildings, terrain, and interference.
相關重要觀念： Key Concepts:
1. 實際信號衰減（Signal Attenuation）： 1. Signal Attenuation:
o 信號強度隨著距離增大而衰減。 o Signal strength decreases as the distance from the base station increases.
o 環境因素（如障礙物、天氣、建築物）會進一步影響信號的覆蓋形狀。 o Environmental factors such as obstacles, weather, and buildings further influence the signal coverage
2. 覆蓋範圍的扭曲原因： shape.
o 多路徑效應（Multipath Effect）：信號反射、折射和散射會改變信號的強度與方向。 2. Causes of Coverage Distortion:
o 陰影效應（Shadowing Effect）：高建築物或山脈可能遮擋信號，造成死角或弱信號區域。 o Multipath Effect: Signal reflections, refractions, and scattering alter the signal strength and direction.
o 干擾（Interference）：來自其他基地台或設備的信號可能導致覆蓋範圍不穩定。 o Shadowing Effect: Tall buildings or mountains may block signals, creating dead zones or areas with
3. 信號地圖與覆蓋規劃： weak signals.
o 為準確表示覆蓋範圍，實際網路規劃會使用信號強度地圖（Signal Strength Map），即 o Interference: Signals from other base stations or devices may disrupt the stability of the coverage.
以不規則圖形顯示實際信號分佈。 3. Signal Strength Map and Coverage Planning:
o Instead of a circular model, actual network planning relies on signal strength maps that depict the
real-world distribution of signals in irregular patterns.
Example 幫助理解：
假設某基地台在開放區域的覆蓋半徑 RRR 是 2 公里：
 理想情況：在沒有干擾和障礙物的情況下，覆蓋區域是一個半徑 2 公里的圓形。 Example for Better Understanding:
 實際情況： Suppose a base station has a coverage radius RRR of 2 km in an open area:
o 在城市中，建築物阻擋信號可能導致某些方向的覆蓋僅達 1 公里。  Ideal Case: In a perfect environment without interference or obstacles, the coverage area is a circle with a
radius of 2 km.
o 在其他方向（如平坦地區），覆蓋可能延伸至 2.5 公里。
實際覆蓋區域可能類似右圖中的不規則形狀，這需要網路工程師考慮並調整天線配置或增加中繼站。
 Real-World Case:
o In an urban area, buildings may block signals in some directions, reducing coverage to 1 km.
o In open areas like plains, the coverage may extend up to 2.5 km.
與前幾張的可能相關概念：
The actual coverage area might look like the irregular shape shown in the right diagram, requiring adjustments in antenna
1. 前一張提到的圓形細胞模型是理想化的，但這一張進一步指出了現實中覆蓋範圍的變化。
configuration or the addition of relay stations to ensure coverage.
2. 頻率再利用（Frequency Reuse）：
o 由於實際細胞形狀的扭曲，頻率分配需要考慮相鄰細胞間的干擾。
3. 蜂巢狀模型（Hexagonal Model）： Possible Related Concepts from Previous Slides:
o 提供了一種更實際的覆蓋規劃方法，即使細胞形狀扭曲，蜂巢結構能更好地降低重疊與信號干擾。 1. Circular Cell Model: The previous slide introduced the idealized circular model for coverage, while this slide
shows its limitations in real-world scenarios.
2. Frequency Reuse:
o Due to the distortion in actual cell shapes, frequency allocation needs to account for interference
between neighboring cells.
3. Hexagonal Model:
o The hexagonal structure remains useful for network planning, even if the actual cell shapes deviate from
ideal circles, as it reduces overlaps and interference.