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Could anyone help me on the question below?:
“What is the basic difference between H & V polarization of a parabolic dish antenna?”
Khaleque
Could anyone help me on the question below?:
“What is the basic difference between H & V polarization of a parabolic dish antenna?”
>>Antenna polarization refers to the orientation of electric field as it leaves the surface of the antenna. Normally, a radiated energy is what we called electromagnetic energy – which is comprised of 3 components: 1.) magnetic field or the current 2.) electrid field or the voltage and 3.) the direction. In a parabolic dish antenna, it is the orientation of the rectangular waveguide at the back of the dish that determines its polarization. Looking at a typical 2D rectangle it has L and W. Applying this to a waveguide, the width (shorter side of rectangle) is the electric field lines and the Length(longer side) is the magnetic field lines. Simply by looking at the waveguide behind the dish, you’ll know its polarization.
Could anyone help me on the questions below?:
Q.1 What you mean by Co-channel Interference and Adjacent Channel interference?
Q.2 If a CDMA BTS and a GSM BTS are located at a same rooftop and very closed to one another, then what kind of effects may come in GSM BTS?
Hi All,
working on an STM-1 link at 155 mbps. Distance is sub 3 kms however the radios are oprating at 38 ghz. 0.6m antennae with gain of aprox 45 dBi max power out of 16.5 dBm. and BER 10-6 at -63 dBm on RX. Link budget looks good with RSL of about -29 dBm, however we are having trouble predicting rain fade. Its in the ptropics. Anyone got a simple rain fade calculator which gives atenuation in dB given path lenger operating frequency and rain density in mm/hr?
regards,
mike.How do you calculate the sensitivity of the CDMA BTS?
What is CLM?
Hi everybody. I need to do a comparison between coverage plots in GSM 1900 and the results obtained on the drive test. What is the rigth atenuation to be considered in ordered to compare both? Is -6dbm enough for incar atenuation ? or do I need to add something else?
I´ll appreciate any commentLogiciel name: PATHLOSS
Hi all,
Can anybody help me to find a definition about PBGT(Power Budget)in the GSM system.
Thanks.Hello,
From various references, I have come across that Freespace loss between Tx and Rx is assumed to be (as stated above)
FSL(dB)=32.4 + 20LogD + 20LogF
F=frequency in Mhz.
D=Distance in Kilometers.I am trying to figure out the background / originating assumptions of this formula.
Could anyone give me a hint ?
Pathma
it diverted from Friis transmission equation: Pr= Pt Gt Gr(lambda/4pi squR)
hi,
what is the diference between PDH and SDH .Plesiochrone Digital Hierarchy.
Synchronus Digital Hierarchy.
PDH= No synchro.
signal goes from point A to point BSDH= synchro, you can make a big network.
signal goes from point A to point B, C , D , …The trame is standardized. STM1, STM4, … like TDMA, CDMA, …
Can any one help me by answering the question below:
>> Why polarization is needed in the GSM antenna? What would happen if there were no electrical and mechanical polarization?Can anybody give me some hints about how to get MW Link Budget of a specific site??
Thanxhii everybody…
i want to know why waves travels more distance in pdh microwave than sdh microwave for sane set of antenna size and hop length.thanks
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