In wireless communications, the carrier signal is an electromagnetic wave used to transport information through the air. The data transmitted by the carrier signal is modulated, which means that the properties of the carrier (such as its amplitude, frequency, or phase) are altered according to the information to be sent.

This process is essential in all types of wireless networks, including Wi-Fi, radio, television, mobile telephony, among others.

We explain what types of data can be transmitted in the carrier signal in a wireless communication context such as Wi-Fi:

1. Digital Data

• User Information: This includes all types of user-generated data, such as emails, files, streaming video, music, and web or mobile application data.
• Control and Management: Data necessary to manage and maintain the network, including requesting and assigning IP addresses, network configuration, and control messages to establish and maintain the connection.

2. Control Information

• Signaling: Information related to the establishment, maintenance and termination of communications. This includes the exchange of control messages that manage the connection and transmission between the device and the base station or router.
• Authentication and Security: Data that is used to authenticate devices attempting to connect to the network and to secure data transmission, such as encryption keys and other security protocols.

3. Service Information

• Network Identification (SSID on Wi-Fi): The identification of the network you are trying to connect to, transmitted as part of the management packets.
• Network parameters: Information about network characteristics, such as operating channels, signal power, and specific configurations of the type of modulation and coding used.

4. Metadata

• Time and Sync Tags: Data that helps synchronize transmission between the sender and receiver to ensure that packet arrivals are interpreted correctly.
• Network Status Information: Information about the health and status of the network, such as signal quality, network congestion, and other performance indicators.

Common Modulation Methods

To transmit this data, wireless networks use different modulation techniques:

• Amplitude Modulation (AM): Changes the amplitude of the carrier.
• Frequency Modulation (FM): Changes the carrier frequency.
• Phase Modulation (PM): Changes the phase of the carrier.
• Digital Modulation: Such as QAM (Quadrature Amplitude Modulation) and PSK (Phase Shift Keying), which are common in digital technologies such as Wi-Fi.

In summary, the carrier signal in a wireless network transmits a wide variety of data, from user information to data critical to network operation and security.

The efficiency of this transmission depends on how this data is modulated on the carrier and the integrity of the received signal.