Wireless & Mobile Communications Multiple Choice Questions on “3G Cdma2000”.
1. Which of the following has no backward compatibility with 3G Cdma2000?
a) IS-95
b) GPRS
c) IS-95A
d) IS-95B
Answer: b
Clarification: 3G Cdma2000 is based on the original IS-95 and IS-95A CDMA standards, as well as the 2.5G IS-95B air interface. While upgrading, Cdma2000 maintains backward compatibility with existing IS-95, IS-95A and IS-95B equipments. Thus, Cdma2000 allow wireless carriers to introduce a family of new high data rate Internet access capabilities within existing systems.
2. 2G and 2.5G CDMA operators may selectively introduce 3G capabilities at each cell without changing entire base stations and reallocate spectrums.
a) True
b) False
Answer: a
Clarification: Cdma2000 does not require change in entire base station or additional RF equipment. All the changes are made in software or in baseband hardware.
3. Which of the following the first 3G CDMA air interface?
a) IS-95
b) IS-95B
c) Cdma2000 1xRTT
d) CdmaOne
Answer: c
Clarification: Cdma2000 1xRTT is the first 3G air interface. Here, RTT stands for Radio Transmission Technology and 1x indicates that the bandwidth is one times that of the original CdmaOne channel. It is modulated on a single carrier.
4. Within ITU IMT-2000 body, Cdma2000 1xRTT is also known as ____________
a) Cdma2000 1xEV-DO
b) Cdma2000 1xEV-DV
c) IS-95B
d) G3G-MC-CDMA-1X
Answer: d
Clarification: Cdma2000 1xRTT is also known as G3G-MC-CDMA-1X. The initials MC stand for multicarrier. RTT stand for Radio Transmission Technology, a language suggested by IMT-2000 body. Usually, MC and RTT are omitted for convenience.
5. How many users are supported by Cdma2000 1X in comparison to 2G CDMA standard?
a) Half
b) Twice
c) Six times
d) Ten times
Answer: b
Clarification: Cdma2000 support up to twice as many users as the 2G CDMA standard. It also provides the two times the standby time for longer lasting battery life.
6. Cdma2000 works in TDD mode only.
a) True
b) False
Answer: b
Clarification: Cdma2000 works in both FDD and TDD mode. Cdma2000 developed for wide area cellular coverage uses FDD. And TDD is used by Cdma2000 for indoor cordless type applications.
7. Which of the following is not a characteristic of Cdma2000?
a) Adaptable baseband signalling rates
b) Adaptable baseband chipping rates
c) Multicarrier technologies
d) OFDMA
Answer: d
Clarification: Cdma2000 does not use OFDMA technique. OFDMA is used by 4G networks. Cdma2000 uses rapidly adaptable baseband signalling rates and chipping rates for each user. It also provides multi-level keying within same framework.
8. Cdma2000 1xEV was developed by ________
a) Motorola
b) AT&T Laboratories
c) Qualcomm
d) NTT
Answer: c
Clarification: Cdma2000 is an evolutionary advancement for CDMA. It was developed by Qualcomm Inc. It is a proprietary high data rate (HDR) packet standard that can be overlaid upon existing IS-95, IS-95B and Cdma2000 networks.
9. How is bandwidth increased in Cdma2000?
a) Clubbing adjacent radio channels
b) Changing the hardware of base stations
c) Change of spectrum
d) Change of RF equipment
Answer: a
Clarification: The increase in the bandwidth is achieved through clubbing the adjacent radio channels of CdmaOne and using multicarrier technologies. For example, Cdma2000 3xRTT uses these technologies by combining three adjacent 1.25 MHz bandwidth of CdmaOne channels.
10. What are the two options provided by Cdma2000 1xEV?
a) Cdma2000 1xRTT. Cdma2000 3xRTT
b) Cdma2000 1xEV-DO, Cdma2000 1xEV-DV
c) Cdma2000 1xEV-DT, Cdma2000 1xEV-DO
d) Cdma2000 1xRTT, Cdma2000 1xEV-DV
Answer: b
Clarification: Cdma2000 1xEV is an evolutionary upgrade for Cdma2000. It provides two options, for accessing only data (Cdma2000 1xEV-DO) and for both data & voice (Cdma2000 1xEV-DV).
11. Which of the following is not backward compatible with Cdma2000?
a) Cdma2000 1xRTT
b) Cdma2000 3xRTT
c) Cdma2000 1xEV-DO
d) Cdma2000 1xEV-DT
Answer: c
Clarification: Cdma2000 1xEV-DO option provides data rates of about 2.4 Mbps and supports data traffic only. No voice communication is supported. It relaxes the minimum latency requirement. But this mode is not backward compatible with Cdma2000.