The adjustment of 4.1 antenna height
Aerial height is direct with base of the station enclothe limits to concern. Generally speaking, the signal that we measure with the instrument enclothes limits to suffer effect of two direction element:
It is the farthermost distance that aerial place sends point-blank wave to be able to be achieved;
2 it is to arrive at the signal intensity enough of this place to be caught for instrument place.
900MHz mobile is communication of line of sight of close land surface, the farthermost distance that aerial place sends point-blank wave to be able to be achieved (S) concern with the height that controls antenna of post a letter directly, specific relation can simplify as follows:
S=2R(H+h)
Among them: R- earth radius, it is 6370km about;
The center height of antenna of H- radical station;
The aerial height of H- mobile phone or test gear.
please Click here to get our dipole antenna
This shows, base the station is wireless the farthermost distance that signal can achieve (namely base of the station cover range) decide by aerial height.
GSM network is building initial stage, the site is less, to assure to enclothe, base average span gets station antenna taller. As in last few years the rapid development of mobile, base station site is many grow in quantity, had achieved in the urban district about 500m left and right sides stands for. Below this kind of circumstance, we must be reduced base of the station cover range, reduce the height of aerial, can affect our network quality badly otherwise. Its influence basically has the following sides:
A. Word Wu disequilibrium. Base station antenna is exorbitant, can cause what this radical stands to cover range too big, the telephone traffic that causes this radical station thereby is very big, and to it of photograph adjacent base because the station is enclothed lesser and by this base the station is enclothed, telephone traffic is lesser, cannot develop due action, bring about word Wu disequilibrium.
B. The interference inside the system. Base station antenna is exorbitant, can cause stand more wireless interference (basically include the interference that be the same as frequency and adjacent frequency interference) , cause word, cross talk and have the appearance such as bigger noise, the quality that causes network of whole and wireless communication thereby drops.
C. Gu island effect. Gu island effect is base the station covers sexual issue, when base the station is enclothed when the special landform such as large surface or mountainous area, as a result of the reflex of surface or mountain peak, make base the station is in enclothe the foundation with changeless limits to go up formerly, in " of land of one province or county enlosed by that of another of occurrence " of very far place, and the look that has switch concern to it adjacent radical stands however because of landform hold back do not enclothe, create " of " land of one province or county enlosed by that of another and appearance so concern without switch between adjacent radical station, "" of land of one province or county enlosed by that of another makes island of a Gu accordingly, take up when the mobile phone on when " of " land of one province or county enlosed by that of another enclothes the signal of the area, because do not have switch,concern very easily and cause a word.
please Click here to get our dipole antenna
The adjustment of 4.2 antenna pitch angle
The adjustment of aerial pitch angle is the network optimizes a medium very important thing. The pitch angle with right choice can make aerial reachs this village attrib border ray and antenna come aerial is in between the ray that suffers interference village border the part with the largest change of attenuation of the gain in perpendicular direction graph, make suffer those who disturb a village to be decreased with frequency and adjacent frequency interference thereby to the smallest; Additional, the choice covers range suitably, make base the station covers limits and expectant design range actually identical, enhance the signal strength that covers an area originally at the same time.
please Click here to get our dipole antenna
In current mobile network, as a result of base the grow in quantity of the site of the station, make when we are designing urban radical to stand, ask its enclothe limits to be 500M left and right sides about commonly, and the character according to mobile antenna, if do not make aerial has certain pitch angle (or pitch angle slants small) if, criterion base of the station covering range can be more than 500M far, can cause so base the station covers range actually bigger than anticipating limits slants, bring about thereby across is enclothed between village and village, concern of photograph adjacent switch is troubled, interference of the frequency inside the system is serious; On the other hand, if the pitch angle of aerial slants big, can cause base the station covers range actually smaller than anticipating limits slants, cause the signal blind area between the village or weak division, at the same time easy the change that causes condition of aerial direction graph (if be from deformation of a kind of pear grown in Hebei Province spindly) , cause the interference inside serious system thereby. Accordingly, reasonable setting pitch angle is to make sure whole mobile assures basically of network quality.
Generally speaking, the size of pitch angle is OK by the following formula computative:
A/2 of θ =arctg(h/R) ＋
Among them: θ- - the pitch angle of aerial
H- - the height of aerial
R- - of the village cover radius
The perpendicular plane of A- antenna half power horn
Type is on aerial advocate when valve direction aims village brim, reach, in actual tone full employment, spend plus 1-2 on the foundation of the pitch angle angle that reachs from this commonly, make signal is enclothed effectively it is in this village.
The adjustment with 4.3 azimuthal antenna
The adjustment with azimuthal antenna is very heavy to the network quality of mobile
please Click here to get our dipole antenna
Our other product:
