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Ranging in Wimax

The initial range is the process of estimating the distance or propagation time between a transmitter and a receiver. Area information can be used to assist in setting operating parameters for the transmitter and receiver. Since each MS has a unique distance from the base station, it is critical in the uplink to synchronize the … Read more

EVDO reverse Link

Here I write about EVDO (HSD) reverse channel in short or summarize defination. The EVDO channels for the reverse connection have a similar structure as for CDMA2000. The reverse link for 1xEV-DO has a structure similar to that for CDMA2000. In EV-DO all signalling is performed on the data channel and this means that there … Read more

CDMA System Time

For both mobiles and base station in direct sequence CDMA must be synchronized. In the IS-95A system, synchronization is based on the Global Positioning Satellite system time. The CDMA system time is the time reference used by all IS-95 / IS-2000 and IS-856 systems. It is synchronous to UTC time (Universal Coordinated Time) except for … Read more

Forward Traffic Channel of CDMA

Forward Traffic Channel is used to Transmit Data and Signaling Information. Symbol repetition makes symbol streams at different rates adapted to those at the rate of 19.2k. The original symbol stream at  the rate of 19.2Kbps will not be repeated, 9.6Kbps symbol stream will be repeated once, 4.8Kbps symbol stream will be repeated twice…. Then, … Read more

Spread Spectrum Concept

Dsss – Direct sequence spread spectrum DSSS – Direct Sequence Spread Spectrum is a spread spectrum technology in which original data is expand using PN code randomly to reduce noise and this also provide high security to data as is scrambled data. Spread spectrum technology spread spectrum technology used in CDMA and Cdma is a … Read more

BENEFITS OF LTE/EPC

Fully packet-oriented mobile broadband network providing: – Peak data rates of 100 Mbps (DL) and 50 Mbps (UL) – Very low latency – Seamless and lossless handover – Sophisticated QoS to support important real time applications such as voice, video and interactive gaming – Support for terminal speeds of 150-500 Km/h and cell ranges of … Read more

What is 3G? or WCDMA?

3G is new upgraded cdma technology, in simple word its Wide band Code Devision Multiple Access Technology (WCDMA). This is first technology in which video call possible means voice and data simultaneously transmitted and received between mobile or data card and BTS – Base Transmission Station. WCDMA Having Below Characterictics Support two basic modes: FDD and … Read more

How Wireless Narrowband Local-Loop Systems in Wimax ?

Naturally, the first application for which a wireless alternative was developed and deployed was voice telephony. These systems, called wireless local-loop (WLL), were quite successful in developing countries such as China, India, Indonesia, Brazil, and Russia, whose high demand for basic telephone services could not be served using existing infrastructure. In fact, WLL systems based … Read more

What is the 3GPP?

The 3rd Generation Partnership Project (3GPP) is a collaboration between groups of telecommunication associations, to make a globally applicable third generation 3G mobile phone system specification within the scope of the International Mobile Telecommunication-2000 project of the International Telecommunication Union (ITU). 3GPP specifications are based on evolved Global Systel for Mobile Communication (GSM) specifications. 3GPP … Read more

Huawei Completes First EHRPD Optimized Handoff Test

Huawei today announced the successful completion of a commercial test for LTE to CDMA evolved, High-Rate Packet Data (eHRPD) optimized handoff. eHRPD means the evolution and improvement of the original CDMA EV-DO network.   eHRPD acts as a bridge from CDMA to LTE by ensuring service continuity while protecting existing operator investment. In the initial … Read more