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Palupi
2011-07-24, 12:01 AM
I want to ask about differencies between RSSI and RSCP? Why on common UE state RSSI rather than RSCP?

zeuscane
2011-07-24, 01:06 AM
RSSI is Rx level before descrembling. It’s just RxLev of UARFCH.
CPICH_RSCP is Rx level after descrembling.
CPICH_Ec/No is result of filtering after dechanalization.
In dBm is: RSCP=RSSI+EcNo.

zeuscane

Irna
2011-07-24, 01:46 PM
RSCP = Received signal code power it is a some of RSSI(Received signal strength) and Ec/No in dbm.

RSCP (dbm) = RSSI(dbm)+Ec/No(dbm).

Characteristics:
1. These quatities will be measured from primary CPICH.To evaluate receive signal condition.
2. RSSI and RSCP is measured for full frequency.
3. Ec/No is measured for a cell on that frequency.

RSCP (Received Signal Code Power) = received power on one code after despreading, defined on pilot symbol

RSSI (Received Signal Strength Indicator) = wideband received power within the channel bandwidth

Ec/No = RSCP divided by the total in the channel bandwidth, i.e. RSCP/RSSI

Eb: Scrambling code energy per bit.
Ec: Scrambling code energy per chip.
Es: Scrambling code energy per chip (as measured by a scanning device during the SCH timeslot scan).
No: Total energy per chip (as measured by a UE).
Io: Total energy per chip (as measured by a scanning device).
Ec/No: Signal-to-noise ratio (as measured by a UE). See 3GPP 25.215, section 5.1.5. Compare No above.
Ec/Io: Signal-to-noise ratio (as measured by a scanning device). Compare Io above.
SIR: Signal-to-interference ratio as measured on the DPCCH. See 3GPP 25.215, section 5.2.2.
RSCP: Received signal code power, identical with Ec: see 3GPP 25.215, section 5.1.5.
RSSI: Received signal strength indicator, identical with No: see 3GPP 25.215, section 5.1.5.

plannerguy
2011-07-25, 06:43 PM
Hi


just simple equation ec/io=rscp/rssi ,so applying log

ec/io=rscp-rssi

or rscp=ec/io+rssi


Regards
Plannerguy

adewijaya
2011-07-25, 07:13 PM
Hi


just simple equation ec/io=rscp/rssi ,so applying log

ec/io=rscp-rssi (from where log function become this equation?) please detail explained :confused:

or rscp=ec/io+rssi

pushp1986
2011-07-25, 09:33 PM
RSCP = Received signal code power it is a some of RSSI(Received signal strength) and Ec/No in dbm.

RSCP (dbm) = RSSI(dbm)+Ec/No(dbm).

Characteristics:
1. These quatities will be measured from primary CPICH.To evaluate receive signal condition.:confused:
2. RSSI and RSCP is measured for full frequency. :o
3. Ec/No is measured for a cell on that frequency.:D

If its is useful plz add reputations is highly appreciated. :victory:

adewijaya
2011-07-25, 09:42 PM
i mean, please describe on calculation formula on equation not only on words :rolleyes:

plannerguy
2011-07-26, 08:38 PM
Hi

ec/io is to expressed in log and is a single factor
rscp in dbm
rssi in dbm

so eq ec/io=rscp/rssi

applying log

log(ec/io)=log(RSCP)-log(RSSI) [now all these are expressed in dBm)

so in general ec/io=rscp-rssi (expressed in dbm)

rscp = rssi +ec/io




Regards
Plannerguy