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IQ data has extensive use in many signal processing contexts, including for radio modulation, software-defined radio, audio signal processing and electrical engineering. I/Q data is a two-dimensional stream. Some sources treat I/Q as a complex number; [1] with the I and Q
In digital modulation, minimum-shift keying (MSK) is a type of continuous-phase frequency-shift keying that was developed in the late 1950s by Collins Radio employees Melvin L. Doelz and Earl T. Heald. [1] Similar to OQPSK, MSK is encoded with bits alternating between quadrature components, with the Q component delayed by half the symbol period.
IQ imbalance is a performance-limiting issue in the design of a class of radio receivers known as direct conversion receivers. [ a ] These translate the received radio frequency (RF, or pass-band ) signal directly from the carrier frequency f c {\displaystyle f_{c}} to baseband using a single mixing stage.
Categorization for signal modulation based on data and carrier types. 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. [1]
A constellation diagram is a representation of a signal modulated by a digital modulation scheme such as quadrature amplitude modulation or phase-shift keying. [1] It displays the signal as a two-dimensional xy-plane scatter diagram in the complex plane at symbol sampling instants.
Barker code used in BPSK modulation In wireless communications, sequences are usually chosen for their spectral properties and for low cross correlation with other sequences likely to interfere. In the 802.11 standard, an 11-chip Barker sequence is used for the 1 and 2 Mbit/s rates.
Frequency mixer symbol. In electronics, a mixer, or frequency mixer, is an electrical circuit that creates new frequencies from two signals applied to it.In its most common application, two signals are applied to a mixer, and it produces new signals at the sum and difference of the original frequencies.
Polar modulation was originally developed by Thomas Edison in his 1874 quadruplex telegraph – this allowed 4 signals to be sent along a pair of lines, 2 in each direction. Sending a signal in each direction had already been accomplished earlier, and Edison found that by combining amplitude and phase modulation (i.e., by polar modulation), he ...