Though many of the policy and regulatory issues must be sorted through, the principle of spectrum sharing in the access network continues to gain ground

Sharing of licensed government spectrum with commercial operators is one expression of the trend. Dynamic access to spectrum represents another trend. Mobile access to Wi-Fi is a third example.

Other methods of combining fixed and mobile access also are developing.

Swisscom, for example, is testing the bonding LTE and DSL. In its present tests, Swisscom passes mobile data to the DSL router, which combines the mobile and fixed-line data streams to boost speed. In pilot trials, speeds of 20 Mbps have been demonstrated, and bandwidth is expected to grow in additional tests.

Those efforts go beyond the older concept of shared resources, such as multiple operators using common towers or radios, for example.

Increasingly, the direction is shared access of all wireless assets, a trend that will be more obvious in fifth generation mobile network standards, as well as in methods supporting mobile device use of Wi-Fi. Though mobile devices already can use Wi-Fi, the coming trend will support new ways of combining mobile and Wi-Fi access, often using the Wi-Fi for downlink, while using mobile for uplink, for example.