What is required to build a concrete business plan?

I have a background in semiconductor wireless technology. I am in the process of putting together a business plan but still don't have a concrete idea. I don't have any customers lined up right now, but I am working on my vague idea to create something concrete. How much of an effort is required in coming up with a business plan that can be translated into success? How much marketing research does a person have to undergo in order to make their business plan?

If you visit www.sba.gov you can see information regarding the aspects a business plan should include. You can also visit with your local SCORE or Small Business Development Center can also help you through the steps of putting together your business plan. A business plan will be your map for success. Some of the main parts will include outlining your products/services/management team/financial projections/marketing plan/etc.