
62 ◾ Mobile Evolution: Insights on Connectivity and Service
A selected modulation choice depends on the SNR conditions. e lower-order modulation for-
mats, such as QPSK, do not require a high SNR but have a lower information rate (throughput).
e high-order modulation techniques are applicable under good SNR conditions.
Higher-order modulation schemes, such as 256-QAM, provide capacity improvements for
small cell deployments, under good radio link conditions, and low error vector magnitude (EVM)
values in the PA. Improvements in the linearity of the PA operation, through digital predistortion
(DPD), enables a reduction of EVM. For example, T ...