A tunable dispersion compensator that includes a free propagation region and an adjustment region. The free propagation region includes a first end and a second end, and allows an input lightwave signal having component signals with different wavelengths to propagate from the first end to the second end. The adjustment region directs the input lightwave into portions of the input lightwave, adjusts a characteristic of the portions of the input lightwave signal at the second end, and directs the adjusted portions of the input lightwave signal back towards the first end. The adjusted portions of the input lightwave signal combine at the first end to generate an output lightwave signal having a phase profile that is different from a phase profile of the input lightwave signal.