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Wireless Communication

16 articles

An Introduction to eSIM Technology

This article, drawing from engineering practices with 5G RedCap modules such as the Quectel RG255C-NA00AB, offers a systematic and comprehen…

Summary of 5G/LTE Working Modes

Power management of 5G and LTE modules is a core component in hardware design and BSP driver development. To strike a balance between respon…

Summary of Dual-Band Wi-Fi and BT Communication Multiplexing and Concurrent Technologies

During the evolution of Wi-Fi products, Dual Band (2.4GHz and 5GHz) has become a very common and frequently used term. In communication, whe…

Detailed Explanation of Wi-Fi 6 OFDMA Feature

OFDMA: Short for Orthogonal Frequency Division Multiple Access. OFDM vs OFDMA In Wi-Fi 4, Wi-Fi 5, and even the earlier 802.11a protocols pr…

Correction to My Understanding of Dual-Band WiFi Antenna Multiplexing and a Comparison Between Duplexer and Diplexer

Previously, in another note of mine describing 2.4GHz and 5GHz dual-band WiFi sharing a single antenna for communication, based on my unders…

The Basics of Dipole Antennas and Antenna Gain

According to the book LTE Tutorial: Principles and Implementation: The half-wave dipole antenna is the most fundamental structural unit of a…

Fundamental Phase Modulation Techniques: BPSK, QPSK, and DQPSK

Carrier modulation methods that manipulate phase, such as BPSK and QPSK, are widely used in wireless communications today. The lower-specifi…

Working Principle of IQ Modulation in Wireless Digital Communication

IQ modulation is the foundation of various high-order modulation schemes widely used in LTE and Wi-Fi, such as BPSK, QPSK, 16-QAM, 64-QAM, a…

How is the Antenna Shared Between Dual-Band WiFi and Bluetooth?

This note attempts to gain a more complete understanding of and answer the following three questions related to RF antenna multiplexing (sha…

LTE Module Network Registration Process and APN Settings

To understand the macro-level framework of the network registration process for an LTE module after power-on—ensuring the device can success…

Comparison of LTE CAT 1bis, LTE-M, and NB-IoT

LTE CAT 1bis, LTE-M, and NB-IoT are all LPWAN (Low Power Wide Area Network) wireless communication technologies targeted at the IoT domain, …

Introduction to 802.1X and RADIUS Authentication Basics

!Untitled.png - RADIUS, as defined by 802.1X, is an enterprise-grade network access authentication and management protocol based on a client…

BQB Certification for Bluetooth Devices

What is BQB Certification? BQB stands for Bluetooth Qualification Body. Only products that pass certification by the Bluetooth SIG (Special …

A Comprehensive Summary of Wi-Fi Low-Power Modes and Workflows

Two Power Modes of a STA Generally speaking, a station (STA) supports two distinct power management modes: - Active Mode: In this state, the…

Summary of Wireshark Packet Capture Mechanisms and Usage Tips

Basic Introduction to Wireshark - Wireshark is the world's most widely used open-source packet capture software (formerly known as Ethereal)…

WiFi Over-the-Air Packet Capture Environment Based on Wireshark + Acrylic WiFi Sniffer

Prerequisites: - Install Wireshark and Acrylic WiFi Sniffer software. - A wireless network adapter that supports Monitor mode. - Pre-knowled…