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Weiland86
2014-05-16, 08:06 AM
Hello guys,

I have been trying to understand in detail how to calculate the data rates in GPRS and EDGE ( for the differente CS and MCS) but my pictures does not match, so if someone can support me with this please feel free to explain it...

(TS slot duration, symbol period, number of symbols per time slot, number of bits per symbol, code rate, number of TS used and so on)



Thanks in advance...

auto_art
2014-05-16, 01:19 PM
GPRS
Coding Scheme
Bit Rate
(kbit/s/slot)
Modulation (http://en.wikipedia.org/wiki/Modulation)
Code Rate


CS-1
8.0
GMSK
1/2


CS-2
12.0
GMSK
≈2/3


CS-3
14.4
GMSK
≈3/4


CS-4
20.0
GMSK
1






Technology
Download (kbit/s)
Upload (kbit/s)
TDMA Timeslots allocated (DL+UL)


CSD
9.6
9.6
1+1


HSCSD
28.8
14.4
2+1


HSCSD
43.2
14.4
3+1


GPRS
80.0
20.0 (Class 8 & 10 and CS-4)
4+1


GPRS
60.0
40.0 (Class 10 and CS-4)
3+2


EGPRS (http://en.wikipedia.org/wiki/EGPRS) (EDGE)
236.8
59.2 (Class 8, 10 and MCS-9)
4+1


EGPRS (http://en.wikipedia.org/wiki/EGPRS) (EDGE)
177.6
118.4 (Class 10 and MCS-9)
3+2

Weiland86
2014-05-16, 02:42 PM
Thanks mate,

What i am looking is how to obtain that values based on a formulation, for example considering:
BW channel = 200KHz, we have a period symbol = 1/200KHz, so period symbol = 0.00005 seconds
Frame (8 TS) = 4.61538 ms, TS = 4.61538ms/8 = 0.000576923 seconds
8PSK = 3 bits per symbol
Code rate = 1

So,
number of symbols per TS = 0.000576923 seconds / 0.000005 seconds = 115.3845 symbols per TS
so number of bits per TS = 115.3845 * 3 = 346.1535
so bits per second = 346.1535 / 0.000576923 = 600kbps

what i am doing wrong?
for the different CS and MCS i do not get the match, :/

Thanks in advance




GPRS
Coding Scheme
Bit Rate
(kbit/s/slot)
Modulation (http://en.wikipedia.org/wiki/Modulation)
Code Rate


CS-1
8.0
GMSK
1/2


CS-2
12.0
GMSK
≈2/3


CS-3
14.4
GMSK
≈3/4


CS-4
20.0
GMSK
1






Technology
Download (kbit/s)
Upload (kbit/s)
TDMA Timeslots allocated (DL+UL)


CSD
9.6
9.6
1+1


HSCSD
28.8
14.4
2+1


HSCSD
43.2
14.4
3+1


GPRS
80.0
20.0 (Class 8 & 10 and CS-4)
4+1


GPRS
60.0
40.0 (Class 10 and CS-4)
3+2


EGPRS (http://en.wikipedia.org/wiki/EGPRS) (EDGE)
236.8
59.2 (Class 8, 10 and MCS-9)
4+1


EGPRS (http://en.wikipedia.org/wiki/EGPRS) (EDGE)
177.6
118.4 (Class 10 and MCS-9)
3+2