Tunable Center Frequency Negative Group Delay Filter Using Coupling Matrix Approach

2017 ◽  
Vol 27 (1) ◽  
pp. 37-39 ◽  
Author(s):  
Girdhari Chaudhary ◽  
Yongchae Jeong
Keyword(s):  
Group Delay ◽  
Center Frequency ◽  
Matrix Approach ◽  
Negative Group ◽  
Coupling Matrix ◽  
Negative Group Delay

scholarly journals Reconfigurable Negative Group Delay Circuit with a Low Insertion Loss Using a Coupled Line

2020 ◽  
Vol 20 (1) ◽  
pp. 73-79
Author(s):  
Girdhari Chaudhary ◽  
Yongchae Jeong
Keyword(s):  
Insertion Loss ◽  
Group Delay ◽  
Characteristic Impedance ◽  
Center Frequency ◽  
Pin Diode ◽  
Negative Group ◽  
Coupled Line ◽  
Coupled Lines ◽  
Low Insertion Loss ◽  
Negative Group Delay

This paper presents a design of a transmissive-type, low insertion loss (IL) negative group delay (NGD) circuit with a reconfigurable NGD. The proposed circuit consists of a series transmission lines (TLs) and shunt short-circuited coupled lines where an isolation port is terminated with a parasitic compensated PIN diode. Analytical design equations are derived to obtain the circuit parameters for the predefined NGD and IL. The low IL can be achieved because of the very high characteristic impedance of the short-circuited coupled lines. The TL terminated with a PIN diode is used to achieve the constant center frequency of reconfigurable NGD circuit. For experimental validation, the NGD circuit is designed and fabricated at a center frequency (<i>f</i><sub>0</sub>) of 2.14 GHz. In the measurement, the NGD varies from -0.5 ns to -2 ns with an IL variation of 2.08 to 3.60 dB at <i>f</i><sub>0</sub> = 2.14 GHz. The NGD bandwidth (bandwidth of GD less than 0 ns) varies from 90 MHz to 50 MHz. The minimum input/output return losses are higher than 10 dB for the overall tuning range.

scholarly journals Novel Gysel Power Dividers with Negative Group Delay Characteristics

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Zihui Zhu ◽  
Zhongbao Wang ◽  
Jianhao Zhou ◽  
Te Shao ◽  
Shaojun Fang ◽  
...  
Keyword(s):  
Insertion Loss ◽  
Return Loss ◽  
Group Delay ◽  
Power Divider ◽  
Center Frequency ◽  
Negative Group ◽  
Power Dividers ◽  
Input Matching ◽  
Coupled Lines ◽  
Negative Group Delay

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.

Sign in / Sign up

Export Citation Format

Share Document