The UMTS Network and Radio Access Technology: Air Interface Techniques for Future Mobile Systems
Jonathan P. Castro
Copyright © 2001 John Wiley & Sons Ltd
Print ISBN 0-471-81375-3 Online ISBN 0-470-84172-9

T
HE
UTRA
1

T
RANSMISSION
S
YSTEM

5.1 UMTS S
PECTRUM
A
LLOCATION

The UMTS frequency ranges are part of the world wide spectrum allocation for 3rd or
evolving 2nd generation systems. Figure 5.1 illustrates the representation of the spec-
trum from major regions (e.g. Europe, Japan, Korea, and USA).
'
Ã
'$
Ã
(

Ã
HTTÃÃ9G
Ã
U99
Ã
F
P
S
@
6
Ã
E
6
Q
6
I
Ã
0+]
Ã
BTH '
Ã
A99ÃÃVG
Ã
VHUTÃ
A99ÃÃ9G
Ã
VHUTÃ
DHU!Ã9G
Ã
DHU!ÃVGÃ

1
The UMTS Terrestrial Radio Access.
192 The UMTS Network and Radio Access Technology

Table 5.1 UTRA Frequency Bands in the MS and BS Side
FDD (MHz) TDD (MHz) up- and downlink
Case User equip-
ment
Base station User equip-
ment
Base station
(a) Uplink
(MS to BS) 1920–1980 1920–1980 1900–1920 1900–1920
Downlink
(BS to MS) 2110–2170 2110–2170 2010–2025 2010–2025
Region 2 – e.g. Europe
(b) Uplink
(MS to BS) 1850–1910 1850–1910 1850–1910 1850–1910
Downlink
(BS to MS) 1930–1990 1930–1990 1930–1990 1930–1990
(c) 1910–1930 1910–1930
5.2 R
ADIO
T
RANSMISSION AND
R
ECEPTION
A
SPECTS


FDD and TDD modes as well as keep certain compatibility with GSM, in order to
facilitate multi-mode system designs. This applies, e.g. to the raster distribution where
200 kHz corresponds to all (UE and BS in FDD and TDD modes). Table 5.3 summa-
rizes the specified channel configurations:
The UTRA Transmission System 193
Table 5.3 UTRA Channel Configurations
FDD (MHz) TDD (MHz)
Channel: UE and BS UE and BS
Spacing 5 MHz 5 MHz
Raster 200 kHz 200 kHz
UL N
u
=

5 

(
1
F
uplink
MHz)
0.0 MHz  F
uplink
 3276.6 MHz
Number
DL N
d
= 5  (
1
F

As in the UE or otherwise stated, we specify transmitter characteristics at the BS an-
tenna connector (test port A) with a full complement of transceivers for the configura-
tion in normal operating conditions. When using external apparatus (e.g. TX amplifiers,
diplexers, filters or a combination of such devices, requirements apply at the far end
antenna connector (port B).
5.3.1 Maximum Output Power
5.3.1.1 User Equipment (UE)
At this time detailed transmitter characteristics of the antenna connectors in the UE are not
available; thus, a reference UE with integral antenna and antenna gain of 0 dBi is as-
sumed. For the definition of the parameters to follow we use the UL reference measure-
ment channel (12.2 kbps) illustrated in Table 5.4, other references can be found in [1,2].
Table 5.4 UL Reference Measurement Channel Physical Parameters (12.2 kbps)
FDD TDD
Parameter Level Parameter Level
Information bit rate (kbps) 12.2 Information data rate 12.2 kbps
DPDCH (kbps) 60 RUs allocated 2 RU
DPCCH (kbps) 15 Mid-amble 512 chips
DPCCH/DPDCH (dB) –6 Interleaving 20 ms
TFCI On Power control 2 bit/user
Repetition (%) 23 TFCI 16 bit/user
Inband signalling DCCH 2 kbps
Puncturing level at code
rate 1/3 : DCH / DCCH
5%/0%
194 The UMTS Network and Radio Access Technology

About four UE power classes have been defined (Table 5.5). The tolerance of the
maximum output power is below the suggested level even when we would use multi-
code transmission mode in the FDD and TDD modes.
Other cases applying to the TDD mode from [2] are:

In FDD or TDD BS maximum output power, P
max
, implies the mean power level per
carrier measured at the antenna connector in specified reference conditions. In normal
conditions, BS maximum output power remains within +2 dB and –2dB of the manufac-
turer’s rated output power. In extreme conditions, BS maximum output power remains
within +2.5 dB and –2.5 dB of the manufacturer’s rated output power.
5.3.2 Frequency Stability
Here frequency stability applies to both FDD and TDD modes. The required accuracy
of the UE modulated carrier frequency lies within
±
0.1 ppm when compared to the car-
rier frequency received from the BS. The signals have apparent errors as a result of BS
frequency error and Doppler shift; hence signals from the BS need averaging over suffi-
cient time.
The BS modulated carrier frequency is accurate to within ± 0.05 ppm for RF frequency
generation.
The UTRA Transmission System 195
5.3.3 Output Power Dynamics
5.3.3.1 User Equipment
In the FDD as well as TDD we use power control to limit interference. The Minimum
Transmit Output Power is better than –44 dBm measured with a Root-Raised Cosine
(RRC) filter having a roll-off factor
a = 0.22
and a bandwidth equal to the chip rate.
5.3.3.1.1 Open Loop Power Control
Open loop power control enables the UE transmitter to sets its output power to a spe-
cific value, where in normal conditions it has tolerance of ±9 dB and ±12 dB in extreme
conditions. We defined it as the average power in a time slot or ON power duration de-
pending on the availability. The two options are measured with a filter having a RRC

Transmitter power control range after 10
equal TPC_cmd groups
Transmitter power control range
after 7 equal TPC_cmd groups
1 dB step size 2 dB step size 3 dB step size
TPC_cmd
Lower Upper Lower Upper Lower Upper
+1 +8 +12 +16 +24 +16 +26
0 –1 +1 –1 +1 –1 +1
–1 –8 –12 –16 –24 –16 –26
0,0,0,0,+1 +6 +14 N/A N/A N/A N/A
0,0,0,0,–1 –6 –14 N/A N/A N/A N/A
196 The UMTS Network and Radio Access Technology

5.3.3.1.3 Uplink Power Control TDD
Through the uplink power control, the UE transmitter sets its output power taking into
account the measured downlink path loss, values determined by higher layer signalling
and filter response
a
. This power control has an initial error accuracy of less than

9 dB under normal conditions and

12dB under extreme conditions.
From [2] we define the power control differential accuracy as the error in the UE
transmitter power step, originating from a step in SIR
TARGET
when the parameter
a
= 0.

30 < DSIR
TARGET

9
1

1
For extreme conditions the value is

12.
5.3.3.2 Base Station
In FDD the transmitter uses a quality-based power control on both the uplink and
downlink to limit the interference level. In TDD the transmitter uses a quality-based
power control primarily to limit the interference level on the downlink.
Through inner loop power control in the downlink the FDD BS transmitter has the abil-
ity to adjust the transmitter output power of a code channel in accordance with the cor-
responding TPC symbols received in the uplink. In the TDD inner loop control is based
on SIR measurements at the UE receiver and the corresponding TPC commands are
generated by the UE, although the latte may or does also apply to the FDD.
5.3.3.2.1 Power control steps
The power control step change executes stepwise variation in the DL transmitter output
power of a code channel in response to a corresponding power control command. The
aggregated output power change represents the required total change in the DL trans-
mitter output power of a code channel while reacting to multiple consecutive power
control commands corresponding to that code channel. The BS transmitter will have the
capability of setting the inner loop output power with a step size of 1 dB mandatory and
0.5 dB optional [3]. The power control step and the aggregated output power change
due to inner loop power control shall be within the range illustrated in Table 5.9.
The UTRA Transmission System 197
In TDD, power control steps change the DL transmitter output power in response to a


0.75dB

16dB

24dB
3dB

1dB

24dB

36dB
5.3.3.2.2 Power Control Dynamic Range and Primary CPICH–CCPCH Power
We refer to the difference between the maximum and the minimum transmit output
power of a code channel for a specified reference condition as the power control dy-
namic range. This range in the downlink (DL) has a maximum power

BS maximum
output power of –3 dB or greater, and minimum power

BS maximum output power
of –28 dB or less.
By total power dynamic range we mean the difference between the maximum and the
minimum total transmit output power for a specified reference condition. In this case,
the upper limit of the dynamic range is the BS maximum output power and the lower
limit the lowest minimum power from the BS when no traffic channels are activated.
The DL total power dynamic range is 18 dB or greater [3].
We call Primary CPICH power to the transmission power of the common pilot channel
averaged over one frame and indicated in a BCH. This power is within

– 6 < P
out
 P
RAT
– 3 3.5
P
RAT
– 13 < P
out
 P
RAT
– 6 5
5.3.4 Out-of-Synchronization Output Power Handling

The UE monitors the DPCCH quality to detect L1 signal loss. The thresholds Q
out

and Q
in
specify at what DPCCH quality levels the UE shall shut its power off and
when it may turn its transmitter on, respectively. The thresholds are not defined ex-
plicitly, but are defined by the conditions under which the UE shuts its transmitter
off and turns it on.
Ã
9Q88Cf@pDÃbq7dÃ
6Ã Ã7Ã Ã8Ã ÃÃ9Ã @Ã
UvrÃbdÃ
b %%dÃ
b!!dÃ
b!'dÃ

thresholds are for reference only [1].
Figure 5.2 illustrates the DPCH power level and the shutting off and on, where the re-
quirements for the UE from Refs. [1,2] are that:
The UTRA Transmission System 199

The UE shall not shut its transmitter off before point B.

The UE shall shut its transmitter off before point C, which is T
off
= [200] ms after
point B.

The UE shall not turn its transmitter on between points C and E.
The UE may turn its transmitter on after point E.
5.3.5 Transmit ON/OFF Power
Transmit OFF power state occurs when the UE does not transmit, except during UL
DTX mode (see Figure 5.3). We define this parameter as the maximum output transmit
power within the channel bandwidth when the transmitter is OFF. The requirement for
transmit OFF power shall be better than –56 dBm for FDD and –65 dBm for TDD, de-
fined as an averaged power within at least one time slot duration measured with a RRC
filter response having a roll off factor
a = 0.22
and a bandwidth equal to the chip rate.
8S/LQN
'3'&+
8S/LQN
'3&&+
6rhtrÃPIÃQr
Hvv
ÃÃQr

as the maximum output transmit power within the channel bandwidth when the trans-
mitter states OFF. Its required level shall be better than –79 dBm measured with a RRC
filter response having a roll off
a
= 0.22 and a bandwidth equal to the chip rate.
The time mask transmit ON/OFF defines the ramping time allowed for the BS between
transmit OFF power and transmit ON power. The transmit power level vs. time meets
the mask illustrated in Figure 5.4.
%Ãpuv &%Ãpuv7ÃvuÃthqrvq
PAAÃQr
6rhtrÃPIÃQr

Figure 5.4 BS Transmit ON/OFF template (TDD).
5.3.6 Output RF Spectrum Emissions
5.3.6.1 Occupied Bandwidth and Out of Band Emission
Occupied bandwidth implies a measure of the bandwidth containing 99% of the total
integrated power of the transmitted spectrum, centred on the assigned channel fre-
quency. In the TDD as well as FDD, the occupied channel bandwidth shall be less than
5 MHz based on a chip rate of 3.84 Mcps.
Out of band emissions are unwanted emissions immediately outside the nominal chan-
nel originating from the imperfect modulation process and non-linearity in the transmit-
ter but excluding spurious emissions. A Spectrum emission mask and adjacent channel
leakage power ratio specify out of band emission limits.
5.3.6.2 Spectrum Emission Mask
The UE spectrum emission mask applies to frequencies that are between 2.5 MHz and
12.5 MHz away from the UE carrier frequency centre. The out of channel emission is
specified relative to the UE output power measured in a 3.84 MHz bandwidth. Table
5.12 illustrates UE power emission values, which shall not exceed specified levels.
q
r


v


Ã
v

Ã
"

x
C

Ã
b
q
7

d
DI
PD[
!
!$
"
"$
#
Q

!
!$
&$
QÃ2Ã"(Ãq7
QÃ2Ã"(Ãq7
QÃ2Ã#"Ãq7
QÃ2Ã#"Ãq7
QÃ2Ã" Ãq7
QÃ2Ã" Ãq7

Figure 5.5 BS spectrum emission mask [3].
For example, emissions for the appropriate BS maximum output power, in the fre-
quency range from
D
f = 2.5 MHz to f_offset
max
from the carrier frequency, shall not
exceed the maximum level specified in Table 5.13 [3–4], where:
 D
f = separation between the carrier frequency and the nominal –3 dB point of the
measuring filter closest to the carrier frequency.

F_offset = separation between the carrier frequency and the centre of the measuring
filter.

f_offset
max
= 12.5 MHz or is the offset to the UMTS Tx band edge, whichever is
the greater.
202 The UMTS Network and Radio Access Technology

53
–
15
¼
(
D
f
–
2.715)
30 kHz
* 3.515  Df < 4.0 –26 30 kHz
3.5  Df < 7.5 4.0  Df < 7.5 P – 52 1 MHz
7.5  Df 7.5  Df < Df
max
P – 56 1 MHz
BS maximum output power P < 31 dBm
2.5  Df < 2.7 2.515  Df < 2.715 –22 30 kHz
2.7  Df < 3.5 2.715  Df < 3.515 –22 – 15¼(Df – 2.715) 30 kHz
* 3.515  Df < 4.0 –26 30 kHz
3.5  Df < 7.5 4.0  Df < 7.5 –21 1 MHz
7.5  Df 7.5  Df < Df
max
–25 1 MHz
*
This frequency range ensures that the range of values of
D
f is continuous.

5.3.6.3 Adjacent Channel Leakage Power Ratio (ACLR)
The ratio of the transmitted power to the power measured in an adjacent channel corre-

150 kHz  f < 30 MHz 10 –36
30 MHz  f < 1000 MHz 100 –36
1 GHz  f < 12.75 GHz 1 MHz –30
Measurements integer multiples of 200 kHz.
5.3.6.5 Transmit Modulation and Inter-modulation
The transmit modulation pulse has a RRC shaping filter with roll-off
a
=0.22 in the
frequency domain. The impulse response of the chip impulse filter RC
0
(t) is:
()
() ()


VLQ   FRV 


&&&
&&
WWW
777
5& W
WW
77
ËÛËÛ
p-a+a p+a
ÌÜÌÜ
ÍÝÍÝ
=

code domain error applies only to multi-code transmission, and it shall not exceed
204 The UMTS Network and Radio Access Technology

–15 dB at a spreading factor of 4 for the UE output power parameter having a value
(

–20 dBm) and operating at normal conditions [1].
5.3.6.5.2 Inter-modulation
By transmit Inter-modulation (IM) performance we meant the measure of transmitter
capability to inhibit signal generation in its non-linear elements in the presence of
wanted signal and an interfering signal arriving to the transmitter via the antenna. For
example, user equipment(s) transmitting in close vicinity of each other can produce
inter-modulation products, which can fall into the UE, or BS receive band as an un-
wanted interfering signal.
We define UE inter-modulation attenuation as the output power ratio of wanted signal
to the output power of inter-modulation product when an interfering CW signal adds
itself at a level below a wanted signal. Both the wanted signal power and the IM prod-
uct power measurements use a RRC filter response with roll-off
a
= 0.22 and a band-
width equal to the chip rate. Table 5.16 illustrates IM requirement when transmitting
with 5 MHz carrier spacing.
Table 5.16 Transmit Inter-modulation
Interference signal frequency offset (MHz) 5 10
Interference CW signal level (dBc) –40
Inter-modulation product (dBc) –31 –41
5.4 R
ECEIVER
C
HARACTERISTICS

For the maximum input level, also with BER not exceeding 0.001, Î
or
= –25 dBm/3.84
MHz, and DPCH_Ec/Î
or
= –19 dB.
In the TDD mode reference sensitivity levels for
Ê
DPCH_Ec/Î
or
and Î
or
are 0 dB and
–105 dBm/3.84 MHz, respectively, while the maximum sensitive level requirements are
–7 dB and –25 dBm/3.84 MHz.
5.4.3 Adjacent Channel Selectivity (ACS)
Adjacent Channel Selectivity (ACS) refers to the measure of a receiver’s ability to re-
ceive a W-CDMA signal at its assigned channel frequency in the presence of an adja-
cent channel signal at a given frequency offset from the centre frequency of the as-
signed channel. We define the ACS as the ratio of receive filter attenuation on the as-
signed channel frequency to the receive filter attenuation on the adjacent channel(s) [1].
The ACS shall be better than 33 dB in Power Class 2(TDD), 3 and 4 for the test pa-
rameters specified in Table 5.17, where the BER shall not exceed 0.001.
Table 5.17 Test parameters for Adjacent Channel Selectivity
Parameter Unit Level
DPCH_Ec dBm/3.84 MHz –103
Î
or
dBm/3.84 MHz –92.7
I

Wanted signal
TDD
dBm/3.84 MHz <RefSens> + 3 dB <RefSens> + 3
dB
DPCH_Ec dBm/3.84 MHz –114 –114
Î
or
dBm/3.84 MHz –103.7 –103.7
I
blocking
(modulated)
applies to FDD and TDD
dBm/3.84 MHz –56 –44
F
uw
(offset) FDD and TDD MHz 10 15
Table 5.19 Out of Band Blocking FDD
Parameter Unit Band 1 Band 2 Band 3
DPCH_Ec dBm/3.84 MHz –114 –114 –114
Î
or
dBm/3.84 MHz –103.7 –103.7 –103.7
I
blocking
(CW) dBm –44 –30 –15
F
uw
MHz
2050<f <2095
2185<f <2230

1< f <1815
2110< f <12750
F
uw
MHz 1790 < f < 1835
2005 < f < 2050
1765 < f < 1790
2050 < f < 2075
1 < f < 1765
2075 < f < 12750
F
uw
MHz 1850 < f < 1895
1945 < f < 1990
1825 < f < 1850
1990 < f < 2015
1 < f < 1825
2015 < f < 12750
The TDD out of band blocking differs from the FDD because they do not have the same
frequency range allocation.
5.4.5 Spurious Response
Through the spurious response, a receiver has the ability to receive a desired signal on
its assigned channel frequency, without exceeding a given degradation originating from
an undesired CW interfering signal. The latter occurs at any other frequency at which
the blocking limit is not met. Table 5.21 illustrates the spurious responses, where the
BER does not exceed 0.001.