How Modulation-QPSK in CDMA ?

     In an actual application, the system implements the modulation in this way:  as shown above, I and Q channel sequences in the figure represent two channels of cyclic PN

How Frame Structure in Wimax ?

The physical frame includes the downlink sub-frame, uplink sub-frame, TTG, and RTG. The physical frame length and the respective duration of downlink sub-frame and uplink sub-frame are broadcast by the

Which Types of Antennas Used in WIMAX ?

WiMAX antennas, just like the antennas for car radio, cell phone, FM radio, or TV, are designed to optimize performance for a given application. The figure above illustrates the three

OFDM Receiver and How it work for LTE?

The receiver is like in any other radio system the more complicated part. In radio systems and of course also OFDM there are two special points a receiver has to

What is SC-FDMA and how it works in LTE?

One of the major drawbacks of an OFDMA system is, that the transformation of a complex symbol mapped sequence (e.g. BPSK, QPSK, etc.) onto a small set of subcarriers produces

Radio Protocol Architecture in LTE

The EUTRAN radio protocol model specifies the protocols terminated between UE and eNB. The protocol stack follows the standard guidelines for radio protocol architectures (ITU-R M1035) and is thus quite

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:

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

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