4G Explained: What Is LTE?

We’ve all seen the ads from the major carriers touting “the largest 4G network in the country,” but what does that even mean? And what’s the difference between AT&T’s two 4G networks, one that’s LTE and one that’s not? And what is LTE?

The most notable change you’ll experience when moving from a 3G to a LTE device is a dramatic speed upgrade. LTE networks are on average 10 times faster than their 3G counterparts. Sites load faster, Netflix doesn’t pause every five seconds, and apps download at greater speed.

Also Check the Road Map for LTE and HSPA+

Is LTE Performance Good? See the Facts

Firstly, substantial increases in peak LTE speeds do not equate to similar increases in network capacity. LTE maximises the data rate available to end users that experience excellent radio conditions (for example close to a base station). However, mobile users that experience poor signal conditions will continue to achieve relatively poor data rates. Hence, it is only a lucky few within a base station coverage area that will experience data rates approaching the peak rates possible. It is true that these users will increase the average throughput delivered by the base station, but by nowhere near the magnitude suggested by the peak data rates.

LTE Performance

Secondly, the highest LTE speeds are only achieved through the use of  large spectrum allocations – ideally 2x20MHz – which is four times the 2x5MHz spectrum used by W-CDMA and HSPA.

Taken from UnwiredInsight

HSPA+ in the HSPA Roadmap

HSDPA

HSDPA aim to reach high data rates (14.4 Mbit/s) in the DL first. These data rate should be compatible with the DSL standards at that time. In R5 high data rate in UL was not as important as in DL. Key features have been fast scheduling and the introduction of 16-QAM.

HSPA

In R6 HSUPA was added to reach data rates of more than 5 Mbit/s in UL. With the possibility to exchange both signaling and data in both UL and DL on HSPA the first step towards all PS services has been made for limited QoS.

LTE

LTE R8 is the standard of the 4th generation and offers extremely high performance: Data rates in the order of hundreds of Mbit/s, an architecture designed for AIPN and all PS services (no CS possible any more) from the  start, and most low latency times for the user plane and the control plane. MIMO and higher order modulation schemes (64-QAM) are extensively used for LTE. With LTE R9 the data rates will be further extended.

HSPA+

HSPA+ has been planed while the work on LTE was already ongoing and thus has to follow the benchmark set by LTE. R7 not only doubles the data rates of HSPA but also introduced feature like CPC allowing the UE always in all RRC states (also CELL_FACH and XXX_PCH) to fully rely on HSDPA services R7 HSPA+ introduces MIMO and 64-QAM as in LTE. In R8 64-QAM will be combined with MIMO in order to enhance the DL data rate by 50%. As well DL interference cancellation is introduced in R8.