A comparison : WCDMA, HSPA, HSPA+, LTE

The new Era of Mobile communication - 4G LTE

The growing demands on mobile networks to support broadband data services such as high quality video streaming at high spectral efficiencies have driven the need to develop systems such as long term evolution (LTE). Orthogonal frequency division multiplexing (OFDM) and multiple-input multipleoutput (MIMO) are the key air-interface technologies of LTE systems.

LTE is completely an IP based system where packet switching is deployed instead of circuit switching. It supports flexible carrier bandwidths ranging from 1.4 MHz to 20 MHz as well as Frequency Division Duplexing (FDD) and Time Division Duplexing (TDD). The major goals behind the development of LTE includes improving spectral efficiency, lowering costs, improving services and better integration with other open standards. Few of the standards of 3GPP release 8 are listed below.

1. Peak download rates of 326.4 Mbit/s for 4x4 antennas, 172.8 Mbit/s for 2x2 antennas for every 20 MHz of spectrum.
2. Peak upload rates of 86.4 Mbit/s for every 20 MHz of spectrum.
3. All terminals are able to process 20 MHz bandwidth
4. At least 200 active users in every 5 MHz cell.
5. Sub-5ms latency for small IP packets.
6. Increased spectrum flexibility, with spectrum slices as small as 1.5 MHz.
7. Optimal cell size of 5 km, 30 km sizes with reasonable performance, and up to 100 km cell sizes supported with acceptable performance.