Skip to main content

W CDMA

  • WCDMA stands for Wideband Code Division Multiple Access and is the 3G technology that employs the Direct-Sequence Code Division Multiple Access (DS-WCDMA) channel access method and the Frequency Division Duplexing (FDD) method to provide high-speed and high capacity service
  • Third generation (3G) wireless capability has been developed in response to a growing demand in data services
  • There are several different radio access technologies defined within ITU, based on either CDM or TDMA technology. Different regional solutions were proposed as solutions to the requirements of IMT-2000. These included Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA) utilizing Frequency Division Duplex (FDD) and Time Division Duplex (TDD)
  • The fragmentation of the proposals led to the creation of two working groups. One group is known as the Third Generation Partnership Project (3GPP) which is working on the Unified Mobile Telecommunication Standard (UMTS) based on WCDMA.
  • The other group is known as 3GPP2 works on CDMA 2000
  • Organization 3rd Generation Partnership Project (3GPP) has continued that work by defining a mobile system that fulfils the IMT-2000 standard, This system a called Universal Mobile Telecommunication System (UMTS)
  • ITU finally approved a family of five 3G standards which are part of the 3G framework known as IMT-2000. These standards are:
    • WCDMA (UMTS 99)
    • WCDMA (HSPA)
    • CDMA2000
    • TD-CDMA
    • TD-SCDMA
  • WCDMA features two modes:
    • Frequency Division Duplex (FDD): Separately users by employing both codes as well as frequencies. One frequency is used for the uplink, while other is used for downlink
    • Time Division Duplex (TDD): Separates users by employing codes, frequencies and time wherein the same frequency is used for both uplink and downlink
  • WCDMA does no need base station timing synchronization
  • WCDMA provides significant flexibility to provide support of multiple users at independent data rates. The flexibility necessitates the utilization of multiple complex waveforms for validation and test.

Comments

Post a Comment

Popular posts from this blog

Design Engineer at Infineon Bangalore

  Hello Dear Readers, Currently at Infineon Bangalore vacancy for the Design Engineer role. Design analog and mixed-signal modules in CMOS and Smart PowerTechnologies, with a particular focus on achieving high-efficiency power conversion for applications using GaN devices; In your new role you will: Design analog and mixed-signal modules  in CMOS and Smart PowerTechnologies, with a particular focus on achieving high-efficiency power conversion for applications using GaN devices; Design and verify pre-silicon analog/mixed-signal integrated circuit blocks, including incorporating features for testing and quality assurance, and providing support for top-level integration; Assist in defining the requirements  for analog and mixed-signal blocks,aligning them with IP Module architecture, and ensuring compliance with requirements through documentation; Estimate effort and planning design work packages to meet project milestones; Provide essential support to physical design ...
1 comment
Read more

Tutorial on EasyEDA desktop software for PCB and schematic design

In this article, I am going to write a tutorial on how to use EasyEDA desktop application for creating a schematic and for PCB design. One of best advantage of this software is that you can create design offline and can automatically synchronize your design with your online EasyEDA account.  It can be used for circuits simulation, PCB deign and electronics circuits design. You can download EasyEDA desktop application by clicking on following link and it will work on windows 7 or its greater version. They are also releasing soon offline application OSX and Linux users. So keep visiting their website for more information.                                                    https://easyeda.com/page/download So let’s start and see how to design a schematic and PCB using EasyEDA offline desktop application. So first of all lets see how to create a schema...
84 comments
Read more

Engineer II - Analog Design Engineering at Microchip

Hello Dear Readers,   Currently at Microchip  vacancy for Engineer II - Analog Design Engineering role. Job Description: The Mixed Signal Development Group is responsible for delivering analog, digital and mixed-signal IP to divisions within Microchip. We work with leading edge CMOS processes to produce analog integrated circuits for wireline applications. From 112Gb/s+ SERDES to high-speed FEC engines, we enable technology that allows Microchip’s products to interface to the outside world.  Job Descriptions: As a member of the Mixed-Signal Development Group, the candidate will be supervised by a team leader/manager, and be engaged in the design of SERDES/DSP blocks, and other high-speed Digital Signal Processing blocks. This will involve taking a design from initial concept to production form. Throughout you will be mentored and coached by experienced engineers and be exposed to Microchip's Best-In-Class engineering practices. Job Responsibilities: Ramping up o...
2 comments
Read more