Novel Gysel Power Dividers with Negative Group Delay Characteristics

Abstract

A novel Gysel power divider with negative group delay (NGD), good matching, and low insertion loss is proposed. Resistors connected with short-circuited coupled lines (RCSCL) are shunted at output ports of the Gysel power divider to obtain NGD characteristics, and another resistor is shunted at the input port to realize perfect input and output matching. To verify the proposed structure, an NGD Gysel power divider is designed and fabricated. At the center frequency of 1.0 GHz, the measured NGD times for different output ports are −1.94 ns and −1.97 ns, the input/output port return loss is greater than 38 dB, the insertion loss is less than 8.3 dB, and the isolation between output ports is higher than 41 dB. To enhance the NGD bandwidth, two RCSCL networks having slightly different center frequencies are connected in parallel, which provides wider bandwidth with good input matching characteristics.

A compact Gysel power divider with ultra‐wide rejection band and high fractional bandwidth

“…But one of their drawbacks is their undesired harmonics, which have not been suppressed. In, 15 to achieve high input and output matching, resistors connected with short-circuited coupled lines are shunted at input and output ports of the GPD. This circuit has a negative group delay and low insertion loss.…”