CDMA Key Performance Indicator (KPI) Analysis and Evaluation of Network while CDMA DT (Drive Test)
While performing CDMA Drive Test , different radio parameter are captured and saved for further analysis by using analyzer software.The live performance of network can be predicted by using some important parameter which are RX Power, Ec/Io,F-FER,TX Power,TX Adj etc.By viewing the values of above parameter we can categorize the level of network performance.
The strongest pilot strength Ec/Io( dB):
MS Rx power (dBm):
The total power received by the mobile station including interference.
MS Tx power (dBm):
The power transmitted by mobile station while conversation (traffic) and access state
MS Tx Adj (dB):
It is the Ms adjacent parameter in transmitting power.
For 800 MHZ CDMA System,Ms Tx Adj = Tx power + 73 + Rx power
For 1900 MHZ CDMA System, Ms Tx Adj=Tx Power+76+Rx Power
F-FER (%) : Forward Error Rate
1.The strongest pilot strength Ec/Io analysis:
The pilot Ec/Io is is used to measure the forward link coverage performance.Generally the threshold of this parameter is = - 15 dB. For reliable modulation the value of Ec/Io must be greater than -13 dB (i.e Ec/Io>-13dB).
Ec/Io (dB) Range Type of Coverage
+INF ------- -6 Excellent coverage
-6 ---------- -8 Good Coverage
-8 ---------- -10 Average Coverage
-10 ---------- -12 Poor Indoor Coverage
-12 ---------- -15 Poor Outdoor Coverage
-15 ---------- -INF No Coverage
2. The Ms Rx power (dBm) analysis:
Ms Rx power is one of the important radio parameter index to measure the forward coverage deepness .Generally the Ms RSSI is assumed to be -105 dBm. The DT is performed inside the car and the loss due to car is assumed 3 dB.
Rx power (dBm) Range Type of Coverage
+INF ------------ -65 Excellent Coverage
-65 ------------- -75 Good Coverage
-75 ------------- -85 Average Coverage
-85 ------------- -95 Poor Indoor Coverage
-95 -------------- -105 Poor Outdoor Coverage
-105 ------------- -INF No Coverage
3. The Ms Tx power (dBm) analysis :
The Ms Tx power is the index which is used to evaluate the reverse link coverage deepness.Ms maximum transmitting power is 23dBm. Normally 5 dB edge coverage margin is considered.
Tx Power (dBm) Range Type of Coverage
-20 -------------- -INF Excellent
-20 -------------- -10 Good
-10 --------------- 3 Good
3 ----------------- 13 Average
13 ----------------- 23 Poor
+INF -------------- 23 Bad (Ms transmitting at maximum power )
4.The Ms Tx- AdjdB
It measures the closed loop power control adjustment parameter. The value range of Tx AdjdB should be 0 ~ -10 dB . The too low and too high value of Tx AdjdB indicates that there is no balance of forward and rverse link .If Tx AdjdB is too low ,the reverse link is better than forward link or reverse link initial power is too high.If the Tx AdjdB is too high,the forward link is better than reverse link coverage or there will be reverse link interference.
5.F-FER (%)
Forward FER is the performance parameter which is used to measure the forward link quality. The value of FER for ideal voice service is 1%.The data service the FER is little bit high is acceptable.If FER is high the voice quality is bad.
FER (%) Range Type of Coverage
1 -------- -INF Excellent Voice Quality
1 --------- 2 Good Voice Quality
3 --------- 2 Good Voice Quality
5 -------- 3 Tolerable Voice Quality
+INF ---- 5 Poor Voice Quality
Coverage Analysis.
The following parameter are used for coverage performance parameter.The strongest pilot strength Ec/Io( dB):
MS Rx power (dBm):
The total power received by the mobile station including interference.
MS Tx power (dBm):
The power transmitted by mobile station while conversation (traffic) and access state
MS Tx Adj (dB):
It is the Ms adjacent parameter in transmitting power.
For 800 MHZ CDMA System,Ms Tx Adj = Tx power + 73 + Rx power
For 1900 MHZ CDMA System, Ms Tx Adj=Tx Power+76+Rx Power
F-FER (%) : Forward Error Rate
1.The strongest pilot strength Ec/Io analysis:
The pilot Ec/Io is is used to measure the forward link coverage performance.Generally the threshold of this parameter is = - 15 dB. For reliable modulation the value of Ec/Io must be greater than -13 dB (i.e Ec/Io>-13dB).
Ec/Io (dB) Range Type of Coverage
+INF ------- -6 Excellent coverage
-6 ---------- -8 Good Coverage
-8 ---------- -10 Average Coverage
-10 ---------- -12 Poor Indoor Coverage
-12 ---------- -15 Poor Outdoor Coverage
-15 ---------- -INF No Coverage
2. The Ms Rx power (dBm) analysis:
Ms Rx power is one of the important radio parameter index to measure the forward coverage deepness .Generally the Ms RSSI is assumed to be -105 dBm. The DT is performed inside the car and the loss due to car is assumed 3 dB.
Rx power (dBm) Range Type of Coverage
+INF ------------ -65 Excellent Coverage
-65 ------------- -75 Good Coverage
-75 ------------- -85 Average Coverage
-85 ------------- -95 Poor Indoor Coverage
-95 -------------- -105 Poor Outdoor Coverage
-105 ------------- -INF No Coverage
3. The Ms Tx power (dBm) analysis :
The Ms Tx power is the index which is used to evaluate the reverse link coverage deepness.Ms maximum transmitting power is 23dBm. Normally 5 dB edge coverage margin is considered.
Tx Power (dBm) Range Type of Coverage
-20 -------------- -INF Excellent
-20 -------------- -10 Good
-10 --------------- 3 Good
3 ----------------- 13 Average
13 ----------------- 23 Poor
+INF -------------- 23 Bad (Ms transmitting at maximum power )
4.The Ms Tx- AdjdB
It measures the closed loop power control adjustment parameter. The value range of Tx AdjdB should be 0 ~ -10 dB . The too low and too high value of Tx AdjdB indicates that there is no balance of forward and rverse link .If Tx AdjdB is too low ,the reverse link is better than forward link or reverse link initial power is too high.If the Tx AdjdB is too high,the forward link is better than reverse link coverage or there will be reverse link interference.
5.F-FER (%)
Forward FER is the performance parameter which is used to measure the forward link quality. The value of FER for ideal voice service is 1%.The data service the FER is little bit high is acceptable.If FER is high the voice quality is bad.
FER (%) Range Type of Coverage
1 -------- -INF Excellent Voice Quality
1 --------- 2 Good Voice Quality
3 --------- 2 Good Voice Quality
5 -------- 3 Tolerable Voice Quality
+INF ---- 5 Poor Voice Quality
great post thank you click me
ReplyDelete