it's a just an adder which can deal with 2 inputs(each is 11-bit wide) and one carry input. Ripple carry means it will first compute the lowest-important bit(by addition) and provide its one-bit carry out as the input for next bit addition. It just keeps repeat this step for all the 11 bits.
It is just a two 11-bit input adder in its simplest form. It should be listed in any digital IC design books. This type of adder offers the slowest speed due to carry ripple through, but it is simplest and occupies the least area and power.