Tuesday 13 September 2011
CELL_FACH to LTE Mobility
It is our understanding that some of the Cell_FACH enhancement proposals for Release 11 are targeted to make it more attractive to keep UEs longer in the Cell_FACH state than is expected with pre-Rel-11 devices. This expectation that the UEs may stay longer in the Cell_FACH state is in turn motivating the mobility from Cell_FACH state to LTE proposal.
For instance, as the network can already today release the Cell_FACH UE’s RRC Connection with redirection, network may want to redirect UE to the correct RAT and frequency based on the UE measurement. Specifically if the network strategy is to keep the UEs long time in Cell_FACH state, it would make sense to provide the network the tools to manage the UEs’ mobility in that state. In addition, the needs for mobility to LTE are somewhat different from mobility to e.g. GERAN, as the former would be typically priority based while the latter would happen for coverage reasons. Thus, if introduced, the network controlled mobility from UMTS Cell_FACH would be specifically interesting for the UMTS to LTE case.
Will update once I have more info.
Monday 12 September 2011
LTE Rollouts and Deployment Scenarios
Sunday 11 September 2011
Ericsson presentation on Heterogeneous Networks
Saturday 10 September 2011
New '4G Americas' Whitepaper on 'Mobile Broadband Explosion'
Thursday 8 September 2011
Overview on Mobile Broadband (MBB) Technologies
Wednesday 7 September 2011
Enhanced Voice Service (EVS) Codec for LTE Rel-10
The traditional (narrowband) AMR (Adaptive Multi-Rate) codec operates on narrowband 200-3400 Hz signals at variable bit rates in the range of 4.75 to 12.2 kbps. It provides toll quality speech starting at 7.4 kbps, with near-toll quality and better robustness at lower rates and better reproduction of non-speech sounds at higher rates. The AMR-WB (Wideband) codec provides improved speech quality due to a wider speech bandwidth of 50–7000 Hz compared to narrowband speech coders which in general are optimized for POTS wireline quality of 300–3400 Hz. Couple of years back Orange was in news because they were the first to launch phones that support HD-Voice (AMR-WB).
Sunday 4 September 2011
HSPA+ Advanced - Enhancements beyond R10
Related post: HSPA evolution – beyond 3GPP Release 10 - Ericsson
Friday 2 September 2011
Multipoint HSDPA / HSPA
Thursday 1 September 2011
Device to Device communication (FlashLinQ?)
Wednesday 31 August 2011
Ultra Self Organising Networks (UltraSON)
Saturday 27 August 2011
2020: Radio and Mobile Broadband (MBB) Beyond 4G
Friday 26 August 2011
Two interesting NGMN papers on Backhaul
The first one, 'Guidelines for LTE Backhaul Traffic Estimation' document describes how a model is developed to predict traffic levels in transport networks used to backhaul LTE eNodeBs. Backhaul traffic is made up of a number of different components of which user plane data is the largest, comprising around 80-90% of overall traffic, slightly less when IPsec encryption is added. These results reveal that the cell throughput characteristics for data carrying networks are quite different to those of voice carrying networks.
The purpose of second one, 'NGMN Whitepaper LTE Backhauling Deployment Scenarios' is to support operators in their migration from current architectures to new, packet-based backhaul networks. With the introduction of LTE operators need to look at how the backhauling network, the network domain that connects evolved NodeBs (eNBs) to MME and S/P-GW, is capable of adapting to the new requirements, namely the adoption of a packet infrastructure, without disrupting the existing services. This paper introduces some reference architectures, moving from a pure layer 2 topology to a full layer 3 one, discussing some elements to be considered in the design process of a network.
Wednesday 24 August 2011
LTE Advanced HetNet Benefits!
Qualcomm is undisputed leader in the LTE chipsets and have been pushing hard for the next generation LTE-A chipsets. Here is a promotional LTE-Advanced Video on Youtube:
Monday 22 August 2011
MU-MIMO (and DIDO)
Saturday 20 August 2011
Lobbying for more Spectrum
Friday 19 August 2011
Patent Wars Part 2 - Who is suing whom
Wednesday 17 August 2011
Patent Wars!
Tuesday 16 August 2011
Converged Mobile Offload Architectures
Monday 15 August 2011
LTE Spectrum Strategies and Forecasts to 2016
Sunday 14 August 2011
mHealth – Mobile Healthcare; consumer, doctors, healthcare providers, hardware and software tech enablers
Saturday 13 August 2011
4G Refarming Scenarios - Picture
Wednesday 10 August 2011
Self-Evolving Networks (SEN): Next step of SON
Monday 8 August 2011
Radio-over-Fiber (RoF): The existing alternative to Femtocells
Radio over Fiber (RoF) refers to a technology whereby light is modulated by a radio signal and transmitted over an optical fiber link to facilitate wireless access. Although radio transmission over fiber is used for multiple purposes, such as in cable television (CATV) networks and in satellite base stations, the term RoF is usually applied when this is done for wireless access.
In RoF systems, wireless signals are transported in optical form between a central station and a set of base stations before being radiated through the air. Each base station is adapted to communicate over a radio link with at least one user's mobile station located within the radio range of said base station.
RoF transmission systems are usually classified into two main categories (RF-over-Fiber ; IF-over-Fiber) depending on the frequency range of the radio signal to be transported.
a) In RF-over-Fiber architecture, a data-carrying RF (Radio Frequency) signal with a high frequency (usually greater than 10 GHz) is imposed on a lightwave signal before being transported over the optical link. Therefore, wireless signals are optically distributed to base stations directly at high frequencies and converted to from optical to electrical domain at the base stations before being amplified and radiated by an antenna. As a result, no frequency up/down conversion is required at the various base station, thereby resulting in simple and rather cost-effective implementation is enabled at the base stations.
b) In IF-over-Fiber architecture, an IF (Intermediate Frequency) radio signal with a lower frequency (less than 10 GHz) is used for modulating light before being transported over the optical link. Therefore, wireless signals are transported at intermediate frequency over the optical.
Access to dead zones
An important application of RoF is its use to provide wireless coverage in the area where wireless backhaul link is not possible. These zones can be areas inside a structure such as a tunnel, areas behind buildings, Mountainous places or secluded areas such a jungle.
FTTA (Fiber to the Antenna)
By using an optical connection directly to the antenna, the equipment vendor can gain several advantages like low line losses, immunity to lightening strikes/electric discharges and reduced complexity of base station by attaching light weight Optical-to-Electrical (O/E) converter directly to antenna.
Saturday 6 August 2011
Weekend Humour: On Standards and Patents
Friday 5 August 2011
TED talk: Wireless data from every light bulb
Thursday 4 August 2011
Detailed presentation on Femtocell Security from Black Hat 2011
Wednesday 3 August 2011
A look at "Idle state Signalling Reduction" (ISR)
Tuesday 2 August 2011
Cellphone radiation and Cancer
Saturday 30 July 2011
Wi-Fi in Public Transport over LTE
Thursday 28 July 2011
Human Activity Recognition for Personalised services
Interesting article from the NTT Docomo Technical journal.