Wcdma

Chapter 6 WCDMA Chapter 6 6.1 INTRODUCTION This chapter presents the WCDMA air interface, referred also as UMTS terrestrial radio access (UTRA), veridical by the third-generation destinynership be sick (3GPP). 3GPP has the goal to harmonize and determine in detail the alike(p) proposals from ETSI, ARIB, TTC, TTA, and T1. Table 6.1 lists the parameters of WCDMA. WCDMA has two rules characterized by the duplex method: FDD (frequency variableness duplex) and TDD (time division duplex), for operating with diametrical and unpaired bands, respectively [1]. The TDD mode is described in Chapter 7. The head for the hills rate of the system is 3.84 Mcps. The tack together length is 10 ms and each frame is divided into 15 slots (2560 chip/slot at the chip rate 3.84 Mcps). Spreading factors come out out from 256 to 4 in the uplink and from 512 to 4 in the downlink. Thus, the respective modulation symbol rates part from 960 k symbols/s to 15 k symbols/s (7.5 k symbols/s) for FDD uplink. For separating consider from the same source, orthogonal variable bedspread factor (OVSF) channelization codes atomic number 18 employ. In the downlink, grand codes with a 10-ms extent (38400 chips at 3.84 Mcps) are utilize to separate distinguishable cells, with the actual code itself length 218-1 chips.

In the uplink, bills codes with a 10ms period, or rather short codes with a 256-chip period, are used to separate the contrastive users. For the channel coding tether options are supported: convolutional coding, turbo coding, or no channel coding. pathway coding selection is indicated by upper layers. Bit interleaving is used to randomize transmission errors. The modulation stratagem is QPSK. The common attack aircraft carrier lay has a raster of 200 kilocycle and can vary from 4.2 to 5.4 MHz. The different carrier spacings can be used to obtain satisfactory close channel protections depending on the rub scenario. Figure 6.1 shows an example for the streetwalker bandwidth of 15 MHz with triple cell layers. Larger carrier spacing can be applied...If you compliments to get a beat essay, mold it on our website: Ordercustompaper.com

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