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The CORRECT choice is (a) True

To explain: Femtocell Network has the capability to help Macro cell Network ACHIEVE SEAMLESS COVERAGE. It can attain higher network capacity by transmitting over an Internet link.

Correct option is (b) LNA

To ELABORATE: LNA detects the satellite signal relayed from the feed and CONVERTS it to an electric CURRENT, amplifies and LOWER its frequency. The most common device used as an LNA is TUNNEL diode.

Right CHOICE is (c) RM2

The best I can explain: Reliable mobile multicast (RM2) is a reliable multicast PROTOCOL and is used for both WIRED and WIRELESS environments. RM2 guarantees SEQUENTIAL packet delivery to all its multicast members without any packet loss.

The correct answer is (a) MULTICAST home agent

The explanation: Multicast home agent (MHA) is RESPONSIBLE for TUNNELING multicast packets to the MS’s currently subscribed FA. MHA SERVES MSs that are roaming AROUND the foreign networks and are within its service range.

The correct choice is (d) LARGE interference

Best explanation: The combination of a larger SPECTRUM, lower POWER, and pulsed data means that UWB causes less interference than NARROWBAND radio designs while yielding LOW probability of detection and excellent multipath immunity.

Correct answer is (a) True

The best explanation: Mobicast is BASED on a method proposed by the IETF to support multicast over Mobile-IP. To handle the case when an MS is both the source and RECIPIENT of a multicast session, ONE needs to minimize the possibility of rebuilding the COMPLETE multicast tree at each foreign domain the MS visits.

Right answer is (b) Path loss

Best EXPLANATION: The path loss is the loss in signal strength of a signal as it TRAVELS through free space. This value is usually CALCULATED by discounting any OBSTACLES or REFLECTIONS that might occur in its path.

The correct CHOICE is (c) Spot beam

The best explanation: The size of the antenna that generates these beams on earth is related DIRECTLY to the peak gain at the center of the spot beams and the smallest spot beam size. The spot beams are TYPICALLY defined by the contours at 3 or 4 dB down from the peak POWER at the center of the beam.

Right choice is (c) Pulse position MODULATION

Explanation: In TM–UWB, the system uses a modulation TECHNIQUE called pulse position modulation. The TM–UWB transmitter emits ultra-short monocycle wavelets with TIGHTLY CONTROLLED pulse-to-pulse INTERVALS, which are varied on a pulse-by-pulse basis in accordance with an information signal and a channel code.

Right answer is (c) Mobile IPs, core BASED TREES

Best explanation: MMP combines the concepts of Mobile IP and core-based trees (CBT). Here the FORMER CONTROLS communication up to the foreign network, and the latter manages movement of the MSS inside them.

Right choice is (b) MMP

Easy explanation: MMP provides a fast and efficient handoff for MSs in FOREIGN NETWORKS. It also ENABLES location-independent ADDRESSING.

Correct answer is (a) True

The BEST I can explain: Every MS can have only one MHA, which dynamically CHANGES based on the location of the MS, WHEREAS a HA of an MS NEVER changes. The protocol requires that each MHA must be a multicast group member.

Right choice is (c) Rayleigh fading

The best I can explain: The coherent interaction of signals ARRIVING by MANY paths causes the Rayleigh or multipath fading in RF communications. Inside buildings, when continuous sine waves are transmitted WHEREIN the channels exhibit multipath DIFFERENTIAL delays in the nanosecond range, the multipath fading OCCURS naturally.

Right option is (c) HIGH cost

The explanation: Femtocell BASE Stations (F-BSs) are short-range, low-cost, low-power indoor devices to provide service for WIRELESS handsets. F-BS, which looks like WLAN Access POINT (AP), is a small device with at least two wireless and INTERNET interfaces.

Right option is (b) Downlink

The BEST EXPLANATION: In SATELLITE telecommunication, a downlink is the link from a satellite down to one or more ground stations or receivers, and an uplink is the link from a ground station up to a satellite.

Right answer is (C) RM2

To explain: RM2 RELIES on the Internet group management protocol (IGMP) to manage multicast group membership. RM2 is a hierarchical protocol that divides a multicast TREE into subtrees, whereby subcasting within these smaller regions is applied using a tree of retransmission SERVERS.

Correct option is (a) Footprint

Explanation: The GEOGRAPHICAL representation of a SATELLITE’s antenna RADIATION pattern is CALLED a footprint or footprint map. In essence, a footprint of a satellite is the area on Earth’s SURFACE that the satellite can receive from or transmit to.

Correct CHOICE is (b) Transponders

Explanation: A communications SATELLITE’s TRANSPONDER is the SERIES of interconnected units that form a communications channel between the receiving and the transmitting antennas. It is mainly used in satellite communication to TRANSFER the received signals.

Right choice is (b) RMDP

Easy explanation: The RELIABLE multicast data DISTRIBUTION protocol (RMDP) is MEANT to be implemented for USE on the MBONE. It relies on the use of FEC and ARQ information to provide reliable multicast service.

Right answer is (a) DFA

For EXPLANATION I WOULD say: DFAs serve as MULTICAST forwarding agents and are meant to isolate the mobility of the mobile host from the main multicast delivery tree. This hierarchical mobility management APPROACH tries to isolate the mobility of the FAS from the main multicast delivery tree.

Right answer is (d) BSC

Explanation: Similar to UMTS Terrestrial RADIO Access Network (UTRAN) architecture, the Femtocell Network consists of three components: Femtocell Base STATIONS (F-BS), Internet Link, and Femtocell Gateway (FGW).

The correct option is (b) False

To EXPLAIN: The “femto” MEANS 10-15. Coverage of Femtocell Network is MUCH SMALLER than a regular Macro cell Network that is why this name is given. Femtocell Network, INSTALLED by end users at home or in an office environment.

The correct choice is (c) International TELECOMMUNICATIONS Satellite

The best explanation: INTELSAT is a COMMUNICATIONS satellite services provider. INTELSAT operates a fleet of 52 communications satellites, which is one of the world’s LARGEST fleet of commercial satellites.

The correct option is (b) False

To elaborate: UWB technology is appropriate for the high-performance wireless home network, which mandates SUPPORT for large bit rate (50 Mbps), high-speed, affordable connectivity between DEVICES, and simultaneous DATA TRANSMISSION from multiple devices, and full-motion VIDEO capability.

Right answer is (d) Limited jitter REQUIREMENTS

Best explanation: UWB devices are POWER limited because they must coexist on a noninterfering basis with other licensed and unlicensed users across several FREQUENCY bands. For UWB systems USING PPM as their modulation TECHNIQUE, limited jitter requirements could be an issue.

Right answer is (B) 14/11 GHz

The EXPLANATION: The KU band is a portion of the electromagnetic spectrum in the MICROWAVE range of FREQUENCIES ranging from 11.7 to 12.7GHz. (downlink frequencies) and 14 to 14.5GHz (uplink frequencies).

Right answer is (b) OPEN access mode

To explain: In open access mode, all CELLULAR users belong to open subscribers GROUP (OSG) and can access F-BS UNCONDITIONALLY. Several cellular service providers have plans to DEPLOY F-BS for better service quality to cover public hole areas.

The CORRECT choice is (a) Femtocell network

Easiest explanation: Femtocell Network is a small-size MACRO cell network DESIGNED for better INDOOR coverage. It began attracting ATTENTION from both industry and academy in late 2007.

Right choice is (b) Perigee

To EXPLAIN: The POINT where satellite is closest to the EARTH is known as the perigee. Here, the satellite moves at its fastest. The high point of the orbit, when the satellite is moving the SLOWEST is CALLED the apogee.

The correct CHOICE is (b) Tunnel diode

The explanation is: The LNA MUST provide a relatively flat RESPONSE for the frequency range of INTEREST, preferably with less than 1 dB of gain variation. The most common device used as an LNA (LOW noise amplifier) is tunnel diode. It is a highly sensitive, low-noise device.

The correct ANSWER is (b) False

To ELABORATE: The basic element in TM–UWB technology is the MONOCYCLE wavelet. Typically, wavelet pulse widths are between 0.2 and 1.5 nanoseconds, corresponding to CENTER frequencies between 600 MHz and 5 GHz.

The correct option is (a) Closed access mode

To elaborate: In closed access mode, a closed subscribers group (CSG) is set by F-BS owner to allow only small PORTION of cellular users to be served in the Femtocell Network. For EXAMPLE, PEOPLE can install F-BS in their house and only household MEMBERS can access F-BS to attain better service.

Right OPTION is (a) True

Best explanation: Femtocell Network is a so-called “double-win” strategy that brings benefits to both cellular users and cellular PROVIDERS. It provides IMPROVED SEAMLESS coverage and enhanced capacity for cellular users.

Correct option is (c) FGW

Explanation: Femtocell GATEWAY (FGW) is a service provider’s device that acts as a gateway between the Internet and the COMMUNICATION network. One side of FGW connects a LARGE NUMBER of F-BSs via broadband Internet, and the other side of FGW is CONNECTED to the telephony core network.

The correct choice is (a) LITHIUM

To EXPLAIN: Lithium batteries have more power and are lighter in weight. Any mass that could be saved by the use of lighter batteries WOULD allow a corresponding INCREASE in the amount of USEFUL payload equipment.

The correct answer is (a) Circular polarization

Explanation: In helical antenna, the diameter and pitch of the helix are comparable to a wavelength. The antenna FUNCTIONS as a directional antenna radiating a beam off the ENDS of the helix. It RADIATES circularly polarized radio waves. These are USED for satellite communication.

The correct choice is (b) False

The explanation: UWB SYSTEMS are much less complex, SINCE they do not use any radio frequency/intermediate frequency (RF/IF) conversion stages, local oscillators, mixers, and other expensive surface acoustic wave (SAW) FILTERS common to traditional radio TECHNOLOGIES.

The correct answer is (a) Ultra wideband TECHNOLOGY

To elaborate: Ultra-wideband (UWB) technology is ALSO known as impulse or zero-carrier radio technology. It appears to be one of the most promising WIRELESS radio communication technologies of RECENT time.

The correct choice is (b) False

The BEST explanation: Unlike conventional radio systems, which operate within a RELATIVELY narrow BANDWIDTH, the UWB radio system operates across a wide range of the frequency spectrum by transmitting a SERIES of extremely narrow (10–1000 per SECOND) and low-power pulses.