Inter-technology Carrier Aggregation

Another one from the 4G Americas whitepaper of Mobile Broadband explosion:

Carrier aggregation will play an important role in providing operators maximum flexibility for using all of their available spectrum. By combining spectrum blocks, LTE-Advanced will be able to deliver much higher throughputs than otherwise possible. Asymmetric aggregation (i.e., different amounts of spectrum used on the downlink versus the uplink) provides further flexibility and addresses the fact that currently there is greater demand on downlink traffic than uplink traffic. Specific types of aggregation include:

• Intra-band on adjacent channels.
• Intra-band on non-adjacent channels.
• Inter-band (e.g., 700 MHz, 1.9 GHz).
• Inter-technology (e.g., LTE on one channel, HSPA+ on another). This is currently a study item for Release 11. While theoretically promising, a considerable number of technical issues will have to be addressed.