MindMap Gallery physical layer
Physical layer mind map, including an overview of the physical layer, Basic knowledge of data communication, transmission media, Channel multiplexing technology, etc.
Edited at 2024-04-02 20:37:46Explore the intricate lineage of the Crown Royal Family Tree, showcasing the House of Windsor and its notable members. From Queen Elizabeth II and Prince Philip's legacy to their childrenKing Charles III, Princess Anne, Prince Andrew, and Prince Edwarddiscover the marriages and offspring that shape the modern monarchy. Notable branches include the heir apparent, Prince William, and his brother, Prince Harry, alongside their families. Delve into Prince Philip's roots in the House of Glücksburg, connecting British royalty to Denmark and Greece. Join us in tracing this remarkable royal heritage!
This is a panoramic infographic—currently sweeping across the web—illustrating the comprehensive applications of OpenClaw, a popular open-source AI agent platform. It systematically introduces this intelligent agent framework—affectionately dubbed "Lobster Farming"—helping readers quickly grasp its core value, technical features, application scenarios, and security protocols. It serves as an excellent introductory guide and practical manual.
這是一張最近風靡全網關於熱門開源AI代理平台OpenClaw的全網應用全景圖解。它系統性地介紹了這款被稱為「養龍蝦」的智慧體框架,幫助讀者快速理解其核心價值、技術特性、應用場景及安全規範,是一份極佳的入門指南與實操手冊。此圖主要針對希望利用AI建構自動化工作流程的技術從業人員、中小企業主及效率追求者,透過9大模組層層遞進,全面剖析了OpenClaw從概念到落地的整個過程。 圖中核心內容首先釐清了「養龍蝦」指涉的是OpenClawd開源智能體,並強調其本質是「AI基建」而非一般聊天機器人。隨後詳細比較其與傳統AI助理的區別,擁有記憶管理、權限控制、會話隔離和異常恢復四大基礎能力,支援跨平台存取和多模型相容(如GPT、Claude、Ollama)。同時,圖解提供了完整的部署方案(雲端/本地/Docker),並列舉了辦公室自動化、內容創作、資料收集等五大應用程式場景。此外,還展示了其火爆程度、政府與大廠佈局、安全部署建議及適合/不適合的人群分類。幫助你快速掌握OpenClaw技術架構與應用價值,指導個人或企業建構AI自動化系統,規避資料外洩與權限失控風險,是學習「執行式AI」轉型的權威參考圖譜。
Explore the intricate lineage of the Crown Royal Family Tree, showcasing the House of Windsor and its notable members. From Queen Elizabeth II and Prince Philip's legacy to their childrenKing Charles III, Princess Anne, Prince Andrew, and Prince Edwarddiscover the marriages and offspring that shape the modern monarchy. Notable branches include the heir apparent, Prince William, and his brother, Prince Harry, alongside their families. Delve into Prince Philip's roots in the House of Glücksburg, connecting British royalty to Denmark and Greece. Join us in tracing this remarkable royal heritage!
This is a panoramic infographic—currently sweeping across the web—illustrating the comprehensive applications of OpenClaw, a popular open-source AI agent platform. It systematically introduces this intelligent agent framework—affectionately dubbed "Lobster Farming"—helping readers quickly grasp its core value, technical features, application scenarios, and security protocols. It serves as an excellent introductory guide and practical manual.
這是一張最近風靡全網關於熱門開源AI代理平台OpenClaw的全網應用全景圖解。它系統性地介紹了這款被稱為「養龍蝦」的智慧體框架,幫助讀者快速理解其核心價值、技術特性、應用場景及安全規範,是一份極佳的入門指南與實操手冊。此圖主要針對希望利用AI建構自動化工作流程的技術從業人員、中小企業主及效率追求者,透過9大模組層層遞進,全面剖析了OpenClaw從概念到落地的整個過程。 圖中核心內容首先釐清了「養龍蝦」指涉的是OpenClawd開源智能體,並強調其本質是「AI基建」而非一般聊天機器人。隨後詳細比較其與傳統AI助理的區別,擁有記憶管理、權限控制、會話隔離和異常恢復四大基礎能力,支援跨平台存取和多模型相容(如GPT、Claude、Ollama)。同時,圖解提供了完整的部署方案(雲端/本地/Docker),並列舉了辦公室自動化、內容創作、資料收集等五大應用程式場景。此外,還展示了其火爆程度、政府與大廠佈局、安全部署建議及適合/不適合的人群分類。幫助你快速掌握OpenClaw技術架構與應用價值,指導個人或企業建構AI自動化系統,規避資料外洩與權限失控風險,是學習「執行式AI」轉型的權威參考圖譜。
physical layer
Physical layer overview
characteristic
Mechanical properties
Electrical characteristics
Features
Procedure characteristics
four Q
Choice of physical transmission media
information encoding problem
Performance analysis (transmission speed)
Channel multiplexing
Basic knowledge of data communications
data and signals
Classification
Analog: Continuous
digital: discrete
data to signal
Analog data to analog signal (amplifier, modulator):
Analog data to digital signal (PCM encoder): sampling, quantization, encoding
Digital data to analog signal (modulator): can be through amplitude modulation, frequency modulation or phase modulation
Digital data to analog signal (digital transmitter)
non-return-to-zero encoding
1=-5V, 0=5V
Disadvantage: Transformer cannot be used during the process
Manchester encoding
1=low to high potential jump, 0=high to low potential jump
Disadvantage: The signal rate is twice the data rate (two potentials in one time interval)
Differential Manchester encoding
1=No transition, 0=There is a transition
Data communication system model
Communication Systems
Types of communication
According to the type of signal transmitted: analog, digital
According to transmission media: wired, wireless
According to the way of information exchange: simplex, half-duplex, duplex
Basic parameters of communication system performance
Data rate (bit rate)
Unit: bps
C (data rate) = B (baud rate) log₂V (voltage level)
Symbol rate (baud rate)
Unit: baud
Is the basic unit of the signal. The symbol for the signal is equal to the bit for the data.
Code element length: Use symbols with the same time interval to represent a number, so that the time interval
Code element: Use symbols with the same time interval to represent a number, so that the signals within the time interval
Channel capacity
Maximum data rate of the channel
signal-to-noise ratio
=S (signal power)/N (noise power)
Usually expressed in logarithmic form: 10lg (S/N)
Unit: 10lg (signal-to-noise ratio) dB
Signal-to-noise ratio 1000 is 30dB
Channel bandwidth
The frequency range that the channel can pass
low pass, band pass, high pass
limited bandwidth signal
Signal bandwidth: Any signal can be transformed into the sum of multiple sine waves through Fourier transform
Channel bandwidth
The ultimate capacity of the channel
Nye's criterion
The maximum symbol rate for a low-pass noiseless channel is equal to twice the channel bandwidth
The maximum symbol rate of a bandpass noiseless channel is equal to the channel bandwidth
Shannon's theorem: C=Wlog₂(1 S/N) bps
C: The limit information transmission rate of the channel, W: Bandwidth
Transmission medium
Wired (guided)
Twisted pair: UTP (unshielded), STP (shielded), RJ connector
coaxial cable
Optical cable: single-mode optical fiber, multi-mode optical fiber, electrical signal-optical signal
Magnetic media
power line
Wireless (non-guided)
Shortwave: reflection from the ionosphere
Terrestrial microwave: transmission in a straight line (large bowl)
Satellite Communications
infrared
Channel multiplexing technology
Signal time domain and frequency domain
FDM (Frequency Division Multiplexing)
TDM (Time Division Multiplexing)
STDM (statistical time division multiplexing)
WDM (Wavelength Division Multiplexing)
CDM (Code Division Multiplexing)