multisection wilkinson power divider

hy everybody and happy new year 2005!

i come again with another question about multi-power wilkinson divider.
These last days, I left a post to know how to calculate the different values and with your help i found a lot of papers and e-books thank a lot!

now i need to know how to calculate the different value of these resistor when i have the value of the impedance of each transmission lines found with the binomial equations?

sory to bother you but i'm not and engineer I am just a passionate person of the domain.

thanks to help me!

Salut guytoub,

I think these 2 papers ae valuable for you. The second one shows examples of 3 to 7-section designs.

Cohn: A class of broadband three-port TEM-mode hybrids (IEEE Trans MTT, Feb 1968)

Abstract�The three-port hyhrid considered in this paper is useful both as a power divider and power combiner. In the divider application, power entering the input port is split equally and with zero phase difference between the output ports. All ports are well matched and the output ports are highly isolated. The generalized form of the hyhrid circuit is a T junction followed by a multiplicity of cascaded pairs of TEM line lengths and interconnecting resistors. Due to symmetry, the resistors are decoupled from the inpnt port, but they serve an essential fnnction in providing ontput-port match and isolation. Each pair of lines and its associated resistor are referred to as a section. The one-section hybrid has been known and widely used, Its usable bandwidth is J,/j, = 1.44:1 for VSWR <1.22 and isolation >20 dB. This paper shows that additional sections can provide a large increase in bandwidth. Some of the examples treated are as follows: two sections, fJfl = 2, VSWR <1.11, isolation> 27 dB; four sections, f,/f, = 4, VSWR <1.10, isolation >26 dB; and seven sections, fq/f, = 10, VSWR <1.21, isolation> 19 dB. Exact design formulas are given for two-section hybrids, and approximate design formulas for three or more sections.

A GENERAL DESIGN FORMULA OF MULTI-SECTION POWER DIVIDER BASED ON SINGLY TERMINATED FILTER DESIGN THEORY

ABSTRACT: A novel design formula of multi-section power divider is derived to obtain wide isolation performance. The derived design formula is based on the singly terminated filter design theory. This paper presents several simulation and experimental results of multisection power divider to show validity of the proposed design formula. Experiments show excellent performance of multi section power divider with multi-octave isolation characteristic .

Regards

Z

thank you zorro!

i've got this papers !

one more question: in the paper of cohn there different values of R and i would like to know how to get the real value in Ω ? for an two sections example there is R1=5.3163 and R2=1.8643 can i say R1= exp 5.3163?

thank a lot

Hi guytoub,

R values are normalized to a suitable value, that is Zo, the impedance at the ports (see figures in Cohn?s paper, where you can see Zo=1 at the ports in fig. 1).
For example, if Zo=50 ohms (as usual), the real value of the resistors whose normalized values are R1=5.3163 and R2=1.8643, are 265.815 and 93.215 ohms respectively.
Best regards

Z

hi zorro!

thanks for your help!
i'll try a test this week !

thank a lot

Can you please resend the paper to me, I can't download it, thansk amillion

how do 4 -8 Ghz

hi all
how we can implement a 2-18 power combiner for sinuous antenna

regrds

thanks

thanks a lot
I am looking for it ^^

for russian users

Added after 2 hours 31 minutes:

can anyone send me this book:
Cohn: A class of broadband three-port TEM-mode hybrids (IEEE Trans MTT, Feb 1968)

Sage_24@tut.by

Please, it's very important for me

thanks

As I remember there is a design example of cascaded broadband wilkinson divider in the MWO. The resistor's vaules and the impedance of the quarter wave section can be optimized against the substrate setup and via holes model.