Lecture

Network and Web: data transmission

Graph Chat

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

Description

This lecture covers different ways to transmit data, including analog and digital signals, frequency-shift keying, Wi-Fi channels, and the relationship between duration and bandwidth. It also discusses the use of dual SSID access points and the concept of SSID. The presentation includes illustrations and references to various modulation techniques and network infrastructures.

Official source

Ontological neighbourhood

Electrical engineering

Telecommunications: Modulation

Related concepts (32)

Frequency modulation

Frequency modulation (FM) is the encoding of information in a carrier wave by varying the instantaneous frequency of the wave. The technology is used in telecommunications, radio broadcasting, signal processing, and computing. In analog frequency modulation, such as radio broadcasting, of an audio signal representing voice or music, the instantaneous frequency deviation, i.e. the difference between the frequency of the carrier and its center frequency, has a functional relation to the modulating signal amplitude.

Frequency-shift keying

Frequency-shift keying (FSK) is a frequency modulation scheme in which digital information is encoded on a carrier signal by periodically shifting the frequency of the carrier between several discrete frequencies. The technology is used for communication systems such as telemetry, weather balloon radiosondes, caller ID, garage door openers, and low frequency radio transmission in the VLF and ELF bands. The simplest FSK is binary FSK (BFSK), in which the carrier is shifted between two discrete frequencies to transmit binary (0s and 1s) information.

Phase-shift keying

Phase-shift keying (PSK) is a digital modulation process which conveys data by changing (modulating) the phase of a constant frequency carrier wave. The modulation is accomplished by varying the sine and cosine inputs at a precise time. It is widely used for wireless LANs, RFID and Bluetooth communication. Any digital modulation scheme uses a finite number of distinct signals to represent digital data. PSK uses a finite number of phases, each assigned a unique pattern of binary digits.

Modulation

In electronics and telecommunications, modulation is the process of varying one or more properties of a periodic waveform, called the carrier signal, with a separate signal called the modulation signal that typically contains information to be transmitted. For example, the modulation signal might be an audio signal representing sound from a microphone, a video signal representing moving images from a video camera, or a digital signal representing a sequence of binary digits, a bitstream from a computer.

Amplitude modulation

Amplitude modulation (AM) is a modulation technique used in electronic communication, most commonly for transmitting messages with a radio wave. In amplitude modulation, the amplitude (signal strength) of the wave is varied in proportion to that of the message signal, such as an audio signal. This technique contrasts with angle modulation, in which either the frequency of the carrier wave is varied, as in frequency modulation, or its phase, as in phase modulation.

Related lectures (64)

Signals and Systems: Sampling Theorem and Applications

Discusses the sampling theorem and its applications in signal processing.

Analog Signal Sampling and Modulation

Covers analog signal sampling, modulation techniques, and eye diagram monitoring in optical communication systems.

Impedance Matching and Wireless Communication

Explores impedance matching in passive RF circuits and wireless communication principles, covering analog and digital modulation, power efficiency, and noncoherent detection.

Analog Circuits for Biochip: Wireless Power and Data Transmission

Covers wireless power and data transmission to implanted systems, exploring modulation techniques, pulse modulation, analog modulation, and digital modulation types.

Transition to/from Continuous Time Signals and Passband Modulation