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This lesson talks about the concept of radio frequency and the components of radio frequency circuits

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The concept of radio frequency

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The radio frequency circuit of the mobile phone specializes in processing high-frequency electrical signals,

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including receiving high-frequency signals from base stations in the air,

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and high-frequency signals generated by the mobile phone itself

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Circuits that receive and transmit such high-frequency signals are collectively referred to as radio frequency circuits

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In a radio frequency circuit, the following components are generally included

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Take a look at the picture on the right

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The figure on the right shows the components contained in the RF circuit

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For example, there are antennas and coaxial switches,

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as well as filters and antenna switches

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A chip with a receiving amplifier and a power amplifier for transmitting power amplification

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There is a radio frequency transceiver, which is also called a radio frequency chip

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There is also a baseband CPU in the radio frequency circuit

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The baseband CPU is the control and signal processing part of the entire radio frequency circuit

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In general, there are antennas, coaxial switches, filters, antenna switches,

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power amplifiers, receiving chips, RF chips,

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and baseband processors in the radio frequency circuit

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The RF transceiver has its power supply chip,

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and the power amplifier has its power supply chip

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The receiving amplifier chip needs power supply, and the antenna switch also needs power supply

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In RF circuits, filters, coaxial switches and antennas, they do not need power

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This is the concept of radio frequency and the components of radio frequency circuit

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Next, let's take a look at the components in the RF circuit in the real thing

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For example, this motherboard,

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this is the RF transceiver chip, and this is the main power amplifier

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There are sub-amplifiers, antenna switches, and receiving chips

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In this mobile phone, its radio frequency circuit includes radio frequency transceiver,

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main power amplifier and auxiliary power amplifier

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Look at another phone

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It also has RF chip, main power amplifier, auxiliary power amplifier

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No matter what kind of mobile phone, its RF circuit must have RF transceiver,

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low-frequency power amplifier or mid-high frequency power amplifier, and receiving chip

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This is a certain phone that supports the 5G frequency band

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Its circuit has 5G antenna base, 5G frequency band filter,

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and 5G frequency band receiving and transmitting power amplifier

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It also has a small antenna switch, RF transceiver, power amplifier power supply,

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baseband power supply, and baseband CPU

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This is the concept of radio frequency circuit and the composition of radio frequency circuit

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That's all for this lesson