5:Capacity of Wireless Channels Vireless oundations Example 1:Impact of Frequency Reuse Different degree of frequency reuse allows a tradeoff between SINR and degrees of freedom per user. Users in narrowband systems have high link SINR but small fraction of system bandwidth. Users in wideband systems have low link SINR but full system bandwidth. 。 Capacity depends on both SINR and d.o.f.and can provide a guideline for optimal reuse. Optimal reuse depends on how the out-of-cell interference fraction f(p)depends on the reuse factor p. Fundamentals of Wireless Communication,Tse&Viswanath 85: Capacity of Wireless Channels Fundamentals of Wireless Communication, Tse&Viswanath 8 Example 1: Impact of Frequency Reuse • Different degree of frequency reuse allows a tradeoff between SINR and degrees of freedom per user. • Users in narrowband systems have high link SINR but small fraction of system bandwidth. • Users in wideband systems have low link SINR but full system bandwidth. • Capacity depends on both SINR and d.o.f. and can provide a guideline for optimal reuse. • Optimal reuse depends on how the out-of-cell interference fraction f() depends on the reuse factor 