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3. Functional Description

3.5. Radio

The ESP8089 radio consists of the following main blocks:

•

2.4 GHz receiver

•

2.4 GHz transmitter

•

High-speed clock generators and crystal oscillator

•

Real-time clock

•

Bias and regulators

•

Power management

3.5.1. Channel Frequencies

The RF transceiver supports the following channels according to the IEEE 802.11 b/g/n

standards.

3.5.2. 2.4 GHz Receiver

The 2.4 GHz receiver downconverts the RF signal to quadrature baseband signals and

converts them to the digital domain with two high-resolution high-speed ADCs. To adapt to

varying signal channel conditions, RF filters, automatically-gained control, DC offset

cancelation circuits and baseband filters are integrated into the radio.

3.5.3. 2.4 GHz Transmitter

The 2.4 GHz transmitter upconverts the quadrature baseband signals to 2.4 GHz, and

drives the antenna with a high-powered CMOS power amplifier. The use of digital

calibration further improves the linearity of the power amplifier, enabling a state of art

performance of delivering +20.5 dBm average power for 802.11 b transmission and +16

dBm for 802.11 n transmission.

Additional calibrations are integrated, in order to cancel any imperfections of the radio. The

calibrations include the following:

Table 3-3. Channel Frequencies

Channel No.

Frequency (MHz)

Channel No.

Frequency (MHz)

1

2412

8

2447

2

2417

9

2452

3

2422

10

2457

4

2427

11

2462

5

2432

12

2467

6

2437

13

2472

7

2442

14

2484

Espressif

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2017.06