Balanced power dividers with improved bandwidth using folded lines

In this article, a balanced filtering power divider (FPD) that allows for operational agility of the bandwidth (BW) is presented. The differential-mode power dividing and high common-mode (CM) suppression can be realized by microstrip-to-slotline transition. Two slotline open stubs with different lengths are added in shunt to the main slotline for the transition, which can not only introduce transmission poles for extending and controlling transition BW, but also generate two extra transmission zeros (TZs) near to the passband edges, featuring good filtering response. The two transmission poles can be independently tunable by loading varactors to the open ends of slotline stubs and two TZs will be changed accordingly so that the filtering passband BW is electrically tunable. To verify the theoretical prediction, a prototype of tunable balanced FPD is fabricated and measured. The measured results show that the 3-dB fractional bandwidth (FBW) of the passband varies from 5.6% to 12.6%, meaning more than a double tuning range for the FBW, and the CM suppression is better than 40 dB across the frequency band of interest. K E Y W O R D Sbalanced filtering power divider, bandwidth agility, common mode suppression, differential mode

Section: Introductionmentioning

confidence: 99%

A bandwidth‐agile balanced filtering power divider

Tan

et al. 2019

“…5 Moreover, a modified branch-line structure with internal coupling technique is utilized to enhance the common mode suppression. 5 In addition, the T-shaped resonator in ref. 6 , split ring resonator in ref.…”

Section: Introductionmentioning

confidence: 99%

“…However, due to having no transmission zeros out of the passband the selectivity is poor. To overcome the disadvantage, the quarter wavelength branch lines on the arms are replaced by three quarter wavelength branch lines to obtain two transmission zeros easily . Moreover, a modified branch‐line structure with internal coupling technique is utilized to enhance the common mode suppression .…”

Section: Introductionmentioning

confidence: 99%

Wideband balanced filters with sharp rejection based on coupled lines and stubs

Feng

Yuan

Che

2018

Self Cite

Two novel high selectivity wideband balanced filters based on coupled lines with multiple transmission zeros/poles are proposed in this article. Four and six transmission zeros out of the passband for the differential mode can be achieved and adjusted by the loaded coupled lines independently, resulting in over 15 dB/20 dB out‐of‐band rejection, respectively. In addition, the common mode can be suppressed >15 dB/20 dB over a wide frequency band with five and seven transmission zeros. Two prototypes with 3 dB fractional bandwidths of 56% and 42.7% for the differential mode are designed and fabricated. Good agreements can be observed between measured results and theoretical expectations.

“…Following the rapid development of the 4/5-Generation (4/5G) wireless communication systems, balanced circuits have excellent characteristics of environmental noises suppression, better dynamic range, and lower electromagnetic interference, which are important components for microwave applications. [1][2][3][4][5][6][7] Due to the printed circuit board (PCB) fabrication precisions, the width for the transmission lines and coupled lines are always >0.20 mm, and the characteristic impedance of the transmission lines is always <130 X, so it is very difficult to realize high power division ratio larger than 5. 8 In this letter, a novel 6-port balanced network with high unequal power division ratio based on improved Gysel power divider using shorted coupled lines is proposed.…”

Section: Introductionmentioning

confidence: 99%

Six-port balanced network with high unequal power division ratio using shorted coupled lines

Feng

Che

2018

Self Cite

A novel 6‐port balanced network with high unequal power division ratio using shorted coupled lines is proposed in this letter. The design parameters of the proposed power divider are analyzed according to transmission line theory. Two double‐sided parallel‐strip line 180° phase inverters loaded with 4 isolation resistors are used to realize high isolation for the power dividing output ports. A planar balanced network with bandwidth of 40.5% (power division ratio: 1:10) for the differential mode and wideband 23% common mode suppression is designed and fabricated. The measured results show good agreement with the theoretical expectations.