64851. Which one of the following statements regarding compandor is FALSE?
64852. The quality of a space-link is measured in terms of the __________ ratio.
64853. The useful operational life of INSAT-IB (launched in 1983) is expected to end by
64854. At present, the radio-frequency band mainly used by most satellites is
64855. Orbital disturbances of a geosynchronous satellite are caused by the
64856. Ball bearing can be removed by using:
64857. In a stop-and-wait ARQ system, the transmitting terminal
64858. A geostationary satellite is one which
64859. The geostationary communication satellite APPLE is parked in the equatorial orbit at
64860. Power received from Sun per m2 surface area of a geosynchronous satellite in nearly __________ watt.
64861. A certain sound has 10000 times more energy than another sound. The number of times it would sound stronger to a listener is
64862. While keeping the down-link frequency constant, the diameter of a satellite antenna is reduced by half. To offer the same EIRP over the increased coverage area, the RF output power has to be increases by a factor of
64863. A communication satellite is a repeater between
64864. The ending part of the popular teleserial Mahabharat will be beamed to the viewers
64865. The most effective anti jamming technique is
64866. For satellite communication, standard Earth stations have antenna diameters in the range of __________ metre.
64867. The Sun blots out the transmission of a geosynchronous satellite twice a year when satellite passes directly in front of it. This outage lasts for about
64868. In satellite communication, frequency modulation is used because satellite channel has
64869. In the case of a 70-MHz IF carrier for a transponder bandwidth of 36 MHz, energy must lie between MHz.
64870. Which of the following factor does NOT contribute to the drift of a geostationary satellite from its stationary position in space?
64871. In communication satellites, the up-link normally operates at a higher frequency than the down-link because it
64872. For global communication, the number of satellites needed is
64873. The noise temperature of sky is about __________ °K.
64874. Assuming earth to be a sphere of radius 6400 km and height of a geosynchronous satellite above Earth as 36000 km, the velocity of a geosynchronous satellite is __________ km/hr.
64875. In the context of error detection in satellite transmission, ARQ stands for
64876. To cover all inhabited regions of the Earth, the number of geosynchronous communication satellites required
64877. The different access methods which permit many satellite users to operate in parallel through a single transponder without interfering with each other as
64878. When a communication satellite passes into Earth's shadow, its temperature drops to about __________ ° K.
64879. In envelope detection of an AM waveform
64880. Shannon's Law relates
64881. India's first three-axis stabilised geostationary communication satellite is
64882. Point out the false statement.
Launching of geostationary experimental communication satellite has helped India to gain experience in
64883. A modem is
64884. In synchronous detection of an AM signal
64885. A typical signal strength received from a geosynchronous communication satellite is of the order of a few
64886. The expression for satellite link frequencies such as 4/6 GHz denotes that
64887. Assuming a minimum angle of elevation of 5°, a geosynchronous satellite remains in line-of-sight for __________ percentage of Earth's surface.
64888. Mark out the WRONG statement.
As compared to FDMA, the demand assignment system TDMA
64889. APPLE was into orbit on 19 th June 1981 by European Space Agency (ESA) from
64890. A telephone user while talking to a person via a satellite has to wait for reply for about __________ millisecond.
64891. Space communication links are being increasingly moved into Ka-band (200-30 GHz) because it
64892. Which of the following statement regarding link loss for a satellite is wrong?
64893. Depending on the technique used, digitized television requires a bit rate between __________ millions.
64894. In selecting a satellite system, the First determining factor is its
64895. Phase modulation is commonly-used for data transmission mainly because
64896. India's Polar Satellite Launch vehicle (PSLV) to be ready in 1991 is designed to launch 1000 kg spacecraft into __________ orbit.
64897. Most of the communication satellites are stationed to the West of their service areas in order to reduce their
64898. The degradation of satellite solar cells with time is mainly due to
64899. The echo heard by a telephone user on a satellite channel can be removed by using
64900. The 1150 kg geosynchronous satellite INSAT-IA parked 36000 km above India had greatly improved India's