Traditional Business Analyst
nBusiness analyst are suppose to be the requirement definer who will be able to define all the requirement of the project from the starting of the project(s). This is the job of Business analyst in tradition requirement analysis. During the traditional software engineering once documented by business analyst are not going to change atleast not without potential delay and budget overruns. He should communicate properly with the customer and refine the needs of the customer. He should be able to satisfy the customer(s) need.
What is Agile Project Management?
This SE assumes that process required to develop working software in todays economy is not predictable. Requirement may change, technology may change we can predict individual team members efficiency. When the factors that affect engineering are not static we can’t predict the outcome within sufficient tolerance. Instead we need to adjust the outcome and guide them to create desired outcome. Agile project management does this by creating a high level visibility of the project status, frequently inspecting outcome and maintain the ability to adapt the changing requirement.

In Agile collaborative project requirement succeeds. All the team members are from all discipline involved in defining project requirement. Technical team members and Quality Assurance (QA) collaborate with the product owner and the BA to develop the project specifications. So Team members in Agile project management can experience the collaborative business process involved in the product engineering.
Then Who is Agile Business Analyst?
Just as every Agile team does not necessarily need a dedicated Project Manager, not every team will need a dedicated Business Analyst. Many Agile projects rely on team members that can perform more than one role. Following are the skills needed for a Agile Business Analyst.

• Like traditional SE Agile Business analyst facilitate discussion with the product owner.
• Afterwards the business analyst should be able bring tremendous amount of technical knowledge that help him to draw out the high level functional requirement from the product owner.
• BAs can also help translate user needs into more technical language for the developers.
• Coaching and team building.
• Developing a good understanding of software architecture concepts will help to bridge the gap between the development team and the business.
• Agile team dynamics and collaborative decision-making techniques.

As a whole even the project can be deliver even without a Project Manager, the Business analyst facilitate, define, understand the team deliver the project with even admit continuous requirement change. That means the Business Analyst should participate in the whole engineering cycle.