Researchers at the newly integrated Nokia-Siemens Networks have doubled
the uplink bandwidth in 4G LTE networks (Long Term Evolution) using
Virtual MIMO (Multiple Input Multiple Output) also known
as SDMA (Space Division Multiple Access).
By using this multiplexing technique, total uplink bandwidth is
increased to 108 megabits per second from 54 megabits without requiring additional
spectrum or equipment on the both the base station and mobile device
while communicating on the same radio channel.
A carrier using an LTE network is able to
utilize spectrum more effectively without needing additional spectrum or equipment,
and will realize increases in network capacity without incurring
additional costs in network infrastructure.
Virtual MIMO/SDMA was successfully put into practice at the 2006 3GSM
World Congress in Hong Kong where researchers streamed a high
definition video stream simultaneously on the uplink and downlink,
while a random data stream was sent in parallel to another device on
the same frequency channel, with total datarates reaching 108 megabits
per second on the uplink, and 160 megabits per second on the downlink
for both devices.