Analytical formulas of noise parameters for inductively source-degenerated LNAs in single-/dual-band configurations were derived using noise transformation matrix recently. In the past, the design optimization of a single-band LNA was achieved by solving the noise equation explicitly in a tedious way. However, it is difficult to optimize LNAs of other configurations such as dual-band, multi-band and broadband topologies because it becomes formidable to solve the noise equation explicitly. Our recent research shows that the noise equation of an LNA can be solved implicitly using noise transformation matrix and an insightful design optimization of a dual-band LNA is thus obtained. The paper reviews all the previous work of single-band LNAs done by others in the literature and then concludes with our experimental results of a dual-band LNA with the balanced noise performance.