1800 Priority

[justdream]

Why we 1800 band has higher priority than 900 band especially in the case of dedicated mode?

[ghassen]

Why we 1800 band has higher priority than 900 band especially in the case of dedicated mode?

it depend of your speed or coverage this not true and depend of your cell priority and cell hierarchy

[RF engineer]

Normally 1800 MHz is non best server strategy which means that in DCS you can make call with low RX level but must be good quality therefore you prioritize is for 1800 band and also this band is used as capacity enhancement not coverage issue .
BR

[ghassen]

Normally 1800 MHz is non best server strategy which means that in DCS you can make call with low RX level but must be good quality therefore you prioritize is for 1800 band and also this band is used as capacity enhancement not coverage issue .
BR

aproximatly same effect as the sectorisation
but you have to consider number of call attemp by surface unit when you are talking about capacity because when we talk about macro and micro cells we must assume the same density of population in both location
also you have to know that micro and macro cell definition is not related to to bandwith that you use it's only related to cell caverage
ie : you can have
900 as micro and 1800 as macro
150 m coverage 500 m coverage
then micro and macro cell nomenclature is only related to the standard and then specifying the maximum cell range
priority is only related to bsc parameter for defining same heirarchy between cel depending on the mobile speed ...

[venom]

Why we 1800 band has higher priority than 900 band especially in the case of dedicated mode?

This secret behind is the propagation of frequencies, 900 propagates more than 1800. The best practice is to define 1800 as a inner band and 900 as an outer band because the broadcast channel (BCCH) can travel to larger area and then takes the traffic from high TA, whereas DCS Sites are not actually the coverage sites, they are basically the capacity sites. But it is not again the hi-fi rule, if ur inter-site distance is less then you can give the clean 1800 frequencies with 900

Now coming back to your question why 1800 is on priority? You know the no. of ARFCNs are greater in 1800 than No. of ARFCNs in 900. That is why you can also make the efficient use of the band with the hopping. (Synthesized or Baseband). Also you can keep your 900 with less traffic which can be used to gather more traffic from high TA. I hope it helps

[ghassen]

This secret behind is the propagation of frequencies, 900 propagates more than 1800. The best practice is to define 1800 as a inner band and 900 as an outer band because the broadcast channel (BCCH) can travel to larger area and then takes the traffic from high TA, whereas DCS Sites are not actually the coverage sites, they are basically the capacity sites. But it is not again the hi-fi rule, if ur inter-site distance is less then you can give the clean 1800 frequencies with 900

Now coming back to your question why 1800 is on priority? You know the no. of ARFCNs are greater in 1800 than No. of ARFCNs in 900. That is why you can also make the efficient use of the band with the hopping. (Synthesized or Baseband). Also you can keep your 900 with less traffic which can be used to gather more traffic from high TA. I hope it helps

concerning the propagation we cannot say that 900 propagate more than the 1800 because it depend on the space where it propagate and you know that if you have less wave length the materials will not stop the wave and for greater wavelength will not propagate into the same material and then for example if you use a 900 cell in a buiding you ll have less coverage than tha 1800 assuming that you use the same power because the 900 will not penetrate the wall as the 1800 do

[venom]

concerning the propagation we cannot say that 900 propagate more than the 1800 because it depend on the space where it propagate and you know that if you have less wave length the materials will not stop the wave and for greater wavelength will not propagate into the same material and then for example if you use a 900 cell in a buiding you ll have less coverage than tha 1800 assuming that you use the same power because the 900 will not penetrate the wall as the 1800 do

Propagation and Penetration both are different things, when i talk about propagation then it means i am talking about reflection, refraction, diffraction, absorption and scattering of a signal. (or in short the distance travelled by a signal).

Wavelength = Phase Speed/Frequency

It means the frequency is inversely proportional to the distance, lower frequency travels more distance.

I agree with you when you talk about penetration, but i am talking generally considering the ideal situation, the behaviour of Radio Waves !!

Obviously if the buildings are close then we need 1800 as a inner band again to have the better penetration but this is for the specific clutter type, In rural things changes completely !!

[ghassen]

I agree, but i am talking generally considering the ideal situation, the behaviour of Radio Waves !!

Obviously if the buildings are close then we need 1800 as a inner band again to have the better penetration but this is for the specific clutter type, In rural things changes completely !!

yes of cours you are right but here i juste wanted to complete your topic by some physics knowledge
please say thanks to lccengr
thank you lccengr

[gprastomo]

Why we 1800 band has higher priority than 900 band especially in the case of dedicated mode?

Hi my friend,

actually it should be depends on operator implementation. According to my experience, the operator has big DCS spectrum than GSM spectrum. So the traffic management should be properly defined and to make frequency plan more easily in case of expansion (DCS expansion is preffered than GSM), basic idea is GSM will serve bad coverage then DCS will serve in good coverage in case of Coosites.
The strategy is like this :
- The DCS will serve traffic as long as the DCS RxLev > -95 dBm otherwise it will be handed over to GSM
- GSM only serve traffic from DCS traffic flow and from the traffic which could not handled by DCS.

We could implement this strategy by modifying C2 of the DCS (applying Cell Reselect Offset for DCS), HO DL/UL threshold for DCS and negatif Handover marging DCS to GSM. This will make DCS more aggresive than GSM as long as the RxLevel > -95 dBm although GSM RxLev more better than DCS RxLev

br

[punto]

@justdream

How many ARFCN you have granted, in 900 MHz and how many in 1800 MHz band ?
P