We describe a 1.28 Tbit/s single-channel transmission in the 1.1 μm band that uses a high-Δ single-mode step-index fiber (SIF) and ytterbium-doped fiber amplifiers (YDFAs). A 650 fs signal pulse was generated from a 10 GHz mode-locked Yb fiber laser (Yb MLFL) that was soliton-compressed by using an anomalous dispersion photonic crystal fiber (PCF). The dispersion of the SIF was compensated over a bandwidth as broad as 2.1 THz with two cascaded chirped fiber Bragg gratings (FBGs). In addition, an enhanced pre-chirping technique was newly adopted for the precise elimination of the large waveform distortion caused by the dispersion slope. As a result, 320 Gbit/s-161 km and 1.28 Tbit/s-58 km transmissions were successfully achieved.