22533 Mobile and Wireless External Oral / Viva Practice Questions with Answers
1). What is the
wireless communication concept?
A). Wireless communication is the transfer of
information between two or more points that are not connected by any physical
medium. Wireless communications can be via Radio communication, Microwave communication,
Light, Visible and Infrared communication.
2). What do you mean by
frequency reuse?
A). Each cellular Base Station is allocated a group
of radio channels to be used. These radio channels can be used by another base
station which is at a suitable distance away from it.
3). What do you mean by
Handoff?
A). When a mobile moves into a different cell while
a conversation is in progress, the Mobile Switching Center automatically
transfers the call to a new channel belonging to the new Base Station. Types of
handoffs are Hard Handoff and Soft Handoff.
4). What do you mean by
Mobile Station Subsystem?
A). It includes mobile equipment which refers o a
physical terminal such as a telephone which includes the radio trans-receiver
signal processor and the Subscriber Identity Module
5). What do you mean by
Base Station Subsystem?
A). It consists of one or more BTS and BSC. Each
BTS is related to one cell which includes an antenna, a video trans-receiver,
and a link to BSC. BSC controls multiple BTS units, manages the handoffs of the
mobiles, and controls the paging.
6). What do you mean by
Network and Switching Subsystem?
A). It controls handoffs between cells in different
BSSs, authenticates users, validates and maintains their accounts. It is mainly
supported by four databases like Home Location Register., Visitor Location
Register, Authentication Center, and Equipment Identity Register.
7). What do you mean by
Ad-hoc networks?
A). Ad-hoc networks are those wirelesses Local Area
Network that does not require any infrastructure to work. Each node can
communicate directly with other nodes. So, no access point is required.
8). What are the
different types of transmission impairment?
A). When the received signal is not as same as the
transmitted signal then it is known as Transmission impairment. Three different
types of transmission impairment
are Attenuation, Noise, and Delay Distortion.
9). What is the
difference between 3G and 4G?
A). 3G stands for a 3rd generation as it is just
that in terms of the evolutionary path of the mobile phone industry. 4G means
4th generation. This is a set of standard that is being developed as a future
successor of 3G in the very near future. 4G speeds are meant to exceed that of
3G. 3G uses the technique of circuit switching while 4G uses the technique of
packet switching.
10). Which multiple
access technique is used by second-generation cellular systems?
A). TDMA/FDD and CDMA/FDD
11) The CDMA standard
of the second-generation network is?
A). IS-95
12). Popular 2G CDMA
standard IS-95 is also known as
A). CdmaOne
13). How many users or
voice channels are supported for each 200 KHz channel in GSM?
A). 8
14). How many
voice channels are supported for each 30 kHz radio channel in IS-136?
A). 3
15). How many users are supported
in IS-95 for each 1.25 MHz?
A). Sixty-four
16). Which
modulation technique is used by GSM?
A). GMSK
17). IS-95 uses which
modulation technique?
A). BPSK
18). IS-136 uses which
modulation technique?
A). π/4 DQPSK
19). The disadvantages
of 2G standards?
A) Limited Internet Browsing
20). GSM (Global System
for Mobile) was earlier also known as
A) Group Special Mobile
21). 2G CDMA standard,
IS-95, was proposed by which company?
A) Qualcomm
22). Which 2G standard
is used in Japan?
A) PDC
23). The 2G GSM
technologies use a carrier separation of
A) 200 kHz