e W is 1.28 megachips per second, and the voice bit rate we are using for this calculation is the information rate R set to 8 kbps with E/No set to 4.5 dB. The data example has R set to 160 kbps, with Eb/No set to 9 dB for rate 1/3 FEC and 10- A major difference between TD-SCDMA and the other CDMA carriers described here is the amount of interference from other cells. Because TD-SCDMA does not have soft Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. Capacity Issues Specific to CDMA Capacity and Quality Principles TABLE 30.5 W-CDMA Summary Parameter values in CDMA capacity estimation Eg/No, Direction Mchps kbits W-CDMA voice W-CDMA voice W-CDMA data 160.0 W-CDMA data 160.0 CDMA capacity estimates One-way Forward Reverse erlangs capacity capacity Erlangs Erlangs Limiting for one sector per MHz sector sector direction carrier 20 MHz per cell W-CDMA voice 130.5 157.4 Forward 119.3 504.2 W-CDMA data Forward handoffs, we expect calls to reach higher levels of intercell interference before they are handed off the hard way. Thus we estimate a higher value for intercell interference, f = 1.0, in the reverse direction. In addition, the forward-direction time division duplex (TDD) allows user terminals to interfere with each other on the TD-SCDMA carrier. This means that there will be interference not just from other base stations at the approximate centers of other cells but also from user terminals that can be much closer. In the absence of real-world ex- perience, we are estimating a forward-direction intercell value of f = 2, but this could be dramatically lower or higher in a TD-SCDMA system. We are using six sectors as an approximation for the adaptive phased arrays (smart antennas) used in TD-SCDMA. We estimate other-sector interference at 30 percent of total signal power, g = 0.3, the same as cdmaOne, cdma2000, and W-CDMA. Orthogonal codes giv