Abstract Spectral amplitude coding optical code division multiple access (SACOCDMA) is a multiplexing technique, which provides faster speed, efficiency, security and unlimited bandwidth. It is widely preferred because of its ability to eliminate multiple access interference (MAI). Free space optics (FSO) provides a wireless link to transmit data securely at higher rates for last mile access. In this work, a 100 Gb/s hybrid FSO-SACOCDMA is designed using direct detection. The performance of FSO using SACOCDMA utilizing NZCC (New Zero Cross Correlation) code is evaluated under different weather conditions (clear weather, haze and fog) for ten users where each user carries 10 Gb/s. The results indicate that in clear weather FSO distance can be extended up to 13 km. Moreover, after using preamplifier in clear weather, FSO enhances the maximum distance to 35 km with acceptable signal to noise ratio and bit error rate. Using an amplifier in the link not only makes the quality of the signal better but it also increases the communication range.