One-Way Electric Line
High Frequency
Two faces Janus
One face is better
The Israel Museum,
Jerusalem
Museum visitor
Professor Michael Bank E-mail: bankmichael1@gmail.com
www.OFDMA-manfred.com and www.SLEINT.com
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High-Frequency One-Wire Line
On high frequencies the A-line is long line submitting to telegraph equitation.
Let us show that B-line idea is correct for the high frequency too.
If so then we can the long line fragment change by one wire line.
Previous simulations where current by ADS program. This program allows simulating
different elements but not electrical lines. For electrical lines simulations was used
delay line.
On height frequencies one can implement CST program. This program allows
simulating different elements including electrical lines.
We can implement one wire line instead of two wires matching lines
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Instead of using two or more channels
+/-
+/-
-/+
-/+
We can use one channel in high frequency systems also
+/+/+/Inverter
-/+
+/Inverter
-/+
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Let us as a prototype (model 1) two wires long line with characteristic
impedance ≈ 300 Ohm
Model 1
1V
Rin = 300 Ohms
0V
30 mm
300 mm
Rout = 300 Ohms
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On frequencies more than one GHz is better to use inverter by Strip Line. This Strip Line
was used on following simulations.
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Model 2
S11
S21
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The matching line is infinitely wide band pass. This is an advantage, but also
disadvantages.
Advantages because you can pass on a long line of multiple signals with different
frequencies.
However, in a real system there is always some noise. Even if he is weak, but in an
infinitely wide band will be infinitely large noise (of course, if the noise is white). Due to
Shannon's theory on such a channel can not transmit information.
Of course, you can apply a filter at the input of the receiver. But this is often problematic.
The filter introduces loss and increases the noise factor.
The proposed single-wire system (B-Line) is a selective system
The disadvantage of B-Line is a need to change the delay line in case of change of
frequency.
B-Line is compatible with the source and load, and in this sense no different from the usual
long line. It is selective, but rather broadband.
It has no requirements of symmetry, which is often a problem when using long line inside
the apparatus.
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MB antenna is the equivalent full dipole, and not halfwave, as is usually applied. In the case of a monopole or
dipole at the end emitters current is equal to zero, and this
dramatically reduces the efficiency of the antennas. At low
frequencies to compensate for this effect is used umbrella
antenna, T-shaped antenna, antenna with top power,
multi-antenna and so on. In contrast to the known
solutions the equivalent of half-wave (or rather the wave)
MB antenna you can see on Fig.
At point A the current is not terminated, it continues to
flow to the source.
Lines AB and CD equipotential, and they can be combined.
Generator “sees” both ends of the system and gives
maximal power. The delay line is small and shielded so that
it does not radiate.
That is, the MBA allows to implement a PCB radiator of
height /2, rather than /4, i.e. the MBA is equivalent to a
full dipole. This result is verified by simulations.
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PCB
Strip Line
Vgout = 1V, Rout = 15 Ohm, Distance 1 m.
E = 9.872 V/m !
This is much more than give a
monopole or dipole
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Let us note some important advantages of high frequency Bline.
• The line is not so critical to the matching with the load resistance.
• It is difficult to achieve ideal symmetrical two wires long line inside of
small device. Non symmetrical can lead to intersymbol interferences For
one wire long line the symmetrical is not a problem.
• Long B-line has a resonance properties. This can help to achieving good
interference immunity. At the same time the line is broadband enough.
• One of useful antennas is dipole, where the presence of the two beams
interfere with the use of dipole as a small device antenna. B-line idea by
MB antenna* can help to solve this problem.
* M. Bank, M. Haridim, V. Tsingouz, Z. Ibragimov, “Highly effective handset
antenna”, Int’l. J. of Communications, 6(2), 2012 (80-87),
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