1xEV-DO Signaling
R&S
®
CMW-KM8xx/-KS8xx
24
User Manual 1173.9511.02 ─ 12
reach the receiving antenna at different times leading to a sum of phase shifted and, if
the receiver is moving, frequency shifted signals.
The internal fading simulator supports propagation conditions defined in the table
6.4.1-1 of 3GPP2 C.S0032 e.g. various vehicle speeds, numbers of paths, path power
settings and delays.
A faded signal has a higher crest factor than an unfaded one. In order to avoid distor-
tion, the baseband signal must be attenuated before entering the fading module, with
the necessary attenuation (insertion loss) depending on the selected fading profile.
In 1xEV-DO signaling, the insertion loss at the baseband level can be calculated auto-
matically or set manually. It is automatically compensated on the HF level, which
implies a shift of the allowed DL power level range to the same extent, but in opposite
direction.
2.2.6.2
AWGN Generator
Additional White Gaussian Noise (AWGN) is typically modeled in receiver tests,
because it may lead to a decrease of throughput. The quality of the received signal is
affected by the ratio of the signal power to the surrounding traffic noise level (signal to
noise ratio). The modulated signals from neighbor cells simply appear as noise. This
effect is simulated by adding AWGN to the signal.
The internal fading module supports AWGN insertion with configurable noise level.
Insertion loss at the baseband level is calculated and compensated automatically at
the HF.
The properties of the AWGN interferer comply with the requirements of 3GPP2
C.S0032, section 6.4.4 (e.g. minimum bandwidth 1.8 MHz, gain flatness 1.0 dB over
the minimum bandwidth, frequency resolution 1 kHz, output range -20 dBm to -95
dBm).
AWGN insertion via the signaling unit is disabled for fading scenarios (see
2.2.7 Connection States
Connection setup and release between the R&S
CMW and an access terminal is a
step-by-step process. This section describes the connection states and transitions.
Table 2-2: Connection states
State
Description
Off
No 1xEV-DO forward signal transmission
On
The R&S
CMW (access network, AN) emulates a 1xEV-DO sector, transmitting a forward
1xEV-DO signal to which the access terminal can synchronize.
The AT may or may not be synchronized to the forward signal, but no session negotiation
has been performed. Session negotiation must be initiated by the AT.
Session Nego-
tiation
A transitory state where AT and the R&S
CMW try to establish a session and negotiate
the session parameters. This state may take a considerable amount of time.
General Description
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