Though RLC (Radio Link Control) layer in LTE is similar to that of UMTS, but still there are some significant differences. One of the big change is RLC LTE header structure for different PDU (Protocol Data Unit) types. When it comes to LTE, RLC can have the following PDU types RLC TMD PDU RLC UMD PDU RLC AMD PDU RLC (more ..)
Power Headroom Report MAC control element tells if UE can transmit at a higher transmission power or not. In basic terms this indicates how much relative transmission power left in the UE. So a simple formula for Power Headroom in LTE is Power Headroom = UE Max Transmission Power – PUSCH Power = Pmax – P_pusch So if Power Headroom (more ..)
While studying the MAC specification today, I thought it would be a good idea to check the MAC Buffer Status Report (BSR) control element details. I had following questions in my mind about Buffer Status Report: Why is this control element used in LTE? What are different BSR CE formats?
Internet of Things is the buzzword and there is no doubt in that in one way or another we all are going to be part of the connected world where not only individuals but practically everything will be connected. But the real question is HOW. Which technology will be the major backbone for this paradigm shift in wireless communication when (more ..)
This tutorial explains how LTE downlink maximum throughput is determined. This is a simple and straightforward formula for data rate calculation. The maximum data rate depends on channel bandwidth. As LTE uses different channel bandwidths both for FDD and TDD. Let’s take the example for LTE using FDD, where channel bandwidth can be 5 MHz, 10 MHz and 20 MHz. (more ..)
A few weeks ago I was looking into an issue related to E911 or Emergency call over the IMS network. Though it appears as most of the concepts related to emergency calls are still same in IMS as compared to legacy systems, such as 3G and GSM, there are many new things are added for IMS. Both in UMTS and (more ..)
According to latest reports Apple iPhone 6 will feature a Qualcomm MDM9625 LTE modem. Though the wireless modem is not the best from Qualcomm and not the latest, still it features some of the best technology options. Here are some of the things you should expect from iPhone 6 modem. Qualcomm MDM9625 Qualcomm MDM9625 features HSPA+ Release 10 and the (more ..)