Comments on “Microstrip T-Junction Power Divider With Exponentially Tapered Transmission Lines”

In the above paper, Smith and Sigmarsson [1] proposed a T-junction unequal power divider using exponentially tapered transmission line (ENTL) and uniform transmission line (UTL). However, the cutoff wavelength $\lambda _{c}$ defined in [1] and also in [2], from which the definition of $\lambda _{c}$ has been adopted, are incorrect. So the entire analysis and design equations of [1] are questionable. Also, the authors have not shown the amplitude and phase imbalance variation over the frequency.