HSDPA

 HSDPA (High Speed Downlink Packet Access) is a wireless network technology that provides high-speed data transfer rates on the downlink, which is the connection from the network to the device. It is an enhancement to the earlier 3G (third-generation) cellular network standard, UMTS (Universal Mobile Telecommunications System).

HSDPA uses a technique called "adaptive modulation" to improve data transfer rates. It adjusts the modulation scheme used to transmit data based on the signal strength and quality of the wireless connection. This allows HSDPA to support data transfer rates of up to 14.4 Mbps (megabits per second), although actual speeds may vary depending on network conditions and device capabilities.

HSDPA has been widely adopted by mobile network operators around the world as a way to offer faster data transfer rates over their 3G networks, before the deployment of 4G LTE. It has been further enhanced by HSPA+ (High Speed Packet Access Plus), which provides even higher data transfer rates by combining HSDPA with HSUPA (High Speed Uplink Packet Access), a technology that improves the data transfer rate on the uplink, which is the connection from the device to the network.