MIMO is effectively radio antenna technology because multiple antennas are used at the transmitter and receiver to allow a variety of signal paths to transmit the data, with separate paths selected for each antenna so that multiple signal paths can be used. The basic mechanism behind MIMO is linear algebra. If we e.g. transmit N … Read more
QoS Mechanisms in Packet Networks There are Three Types of QoS Mechanisms in Packet Networks. Control Plane Mechanisms Data Plane Mechanisms Its Tradeoffs Control Plane Mechanisms Such mechanisms include QoS policy management, signaling, and admission control. QoS policy management is about defining and provisioning the various levels and types of QoS services, as well as … Read more
How Transport Channel Processing in LTE? Transport channels are block oriented transmission services and transmit one or more transport blocks per transmission time interval (TTI). The TTI is 1 ms (e.g. one sub-frame). Transport blocks may in general have variable size. Typically the number of transport blocks that can be transmitted in a TTI depends … Read more
Physical Channel Types of LTE The physical layer uses resource blocks to transmit binary coded information in QPKS, 16QAM or 64QAM or OOK modulation form. Physical channels determine how data is processed and then mapped via dynamical scheduling onto resource blocks. Thus physical channels also in EUTRAN represent the available physical resources. Like transport channels, … Read more
Transport channels are used as the basic transmission service offered by layer 1 to MAC. MAC will use transport channels to multiplex and demultiplex logical channels onto and from them. In contrast to logical channel types, referring to the type of information transmitted, transport channel types are used to indicate the transport characteristics. This means … Read more
Authentication and Access Control in Wimax Access control is the security mechanism to ensure that only valid users are allowed access to the network. In the most general terms, an access control system has three elements: (1) an entity that desires to get access: the supplicant, (2) an entity that controls the access gate: the … Read more
Logical channels are in a one-to-one fashion associated with radio bearers. Logical channel types are used to distinguish the type of information transmitted within the attached radio bearer. The two major groups of logical channel types are therefore control channels for signaling and traffic channels for IP user data. Currently the following logical channel types … Read more
SEATTLE—T-Mobile USA Inc. and its parent company, Deutsche Telecom A.G., have been ordered by the U.S. Department of Labor to pay $345,972 to a worker allegedly fired for being a whistle-blower. Bellevue, Wash.-based T-Mobile said it plans to appeal. The Department of Labor’s order resulted from an investigation into alleged violations of the whistleblower protection … Read more
How to Layer 2 Functions and Data Flow in LTE For layer 2 let us first take a look into the uplink. Data transmission is handled through the protocol stack according to the following flow: 1. Data is generated by either signaling control protocols (RRC, NAS) or by some application on the UE’s IP stack. … Read more
Different Tasks and States of RRC Protocol in LTE-EUTRAN The RRC protocol for EUTRAN is responsible for the basic configuration of the radio protocol stack. But one should note, that some radio management functions (scheduling, physical resource assignment for physical channels) are handled by layer 1 and layer 2 autonomously. MAC and layer 1 signaling … Read more