However, it is more general than soft handoff as it includes active participation by multiple base stations throughout a call. A three dimensional environment presents new opportunities in the area of macrodiversity combining. The quality of the uplink is improved. Artificial multipath is generated on the downlink. Typically all base stations in the Active Set transmit the same power to the mobile unit in soft handoff.
Most studies suggest that the increased interference neutralizes the added diversity.
Traditional Soft Handoff Algorithm Determine the Active Set for each mobile. Assign each traffic channel a small and equal portion of the total traffic power. If the powers begin to oscillate, send a do nothing command. The simulated system consists of 2 antennas per floor in a 2 story building. The transmitted signals undergo path loss, lognormal shadowing, and Rayleigh fading.