Multiband Microwave: It’s Not Just for 80GHz Links – Applications in Traditional Microwave Bands
Multiband backhaul links consist of running multiple channels at different frequency bands on a single link to improve capacity and reliability. Currently there are several products in the market (or in development) that are using a combination of E-band and microwave frequencies. An alternative is to take advantage of the larger channels of higher frequency bands (ex: 32 GHz) and better RF performance of lower frequency bands (Ex: 11 GHz) within the traditional microwave range. These links essentially operate like an extended ACM solution – giving more reliability than higher frequency band and more capacity than the lower frequency channel operating independently. The usefulness of multiband comes when operators design links with the same mindset as ACM –different classes of traffic at different capacity levels each with their own target reliability (to take advantage of the better reliability and capacity levels offered by multiband solution). There will be a range of link distances where multiband makes sense. The goal of this exercise is to understand these distances and figure out conditions under which multiband links make most sense for a combination of frequency bands within traditional microwave frequency range.