In polarization division technique ______ polarization is used.
1.Orthogonal
2.Non orthogonal
3.Orthogonal & Non orthogonal
4.None of the mentioned
In soft decision approach 100 means?
1.Certainly one
2.Certainly zero
3.Very likely zero
4.Very likely one
Adding improvement to the signal subset choice by starting with the densest possible lattice for the space is called as
1.Optimum signal constellation boundaries
2.Higher density lattice structures
3.Trellis coded modulation
4.None of the mentioned
Average effective information is obtained by
1.Subtracting equivocation from entropy
2.Adding equivocation with entropy
3.Ratio of number of error bits by total number of bits
4.None of the mentioned
Channelization characterized by orthogonal spectra is called as
1.Time division multiplexing
2.Frequency division multiplexing
3.Time division & Frequency division multiplexing
4.None of the mentioned
Choosing a closely packed signal subset from any regular lattice or array of candidate points is called as
1.Optimum signal constellation boundaries
2.Higher density lattice structures
3.Trellis coded modulation
4.None of the mentioned
Code’s redundancy is given as
1.n/k
2.k/n
3.nk
4.None of the mentioned
Components used for generation of turbo codes are
1.Inter leavers
2.Punching pattern
3.Inter leavers & Punching pattern
4.None of the mentioned
Decoders are connected in series.
1.True
2.False
Entropy is the measure of
1.Amount of information at the output
2.Amount of information that can be transmitted
3.Number of error bits from total number of bits
4.None of the mentioned
Equivocation is the
1.Conditional entropy
2.Joint entropy
3.Individual entropy
4.None of the mentioned
For a error free channel, conditional probability should be
1.Zero
2.One
3.Equal to joint probability
4.Equal to individual probability
For more than two quantization level, _______ is used.
1.Hard decision
2.Soft decision
3.Hard & Soft decision
4.None of the mentioned
Greater the redundancy lesser is the bandwidth expansion.
1.True
2.False
How can the throughput of the system be increased?
1.Increasing EIRP
2. Increasing channel bandwidth
3.Decreasing system losses
4.All of the mentioned
In double side band spectrum which side-band is called as inverted side-band?
1.LSB
2.USB
3.LSB & USB
4.None of the mentioned
In MFSK, R/W
1.Increases with increase in M
2.Increases with decrease in M
3.Decreases with increase in M
4.Is not dependent on M
In MPSK, R/W
1.Increases with increase in M
2.Increases with decrease in M
3.Decreases with increase in M
4.Is not dependent on M
In soft decision approach 0 represents
1.Certainly one
2.Certainly zero
3.Very likely zero
4.Could be either zero or one
In soft decision approach what does -127 mean?
1.Certainly one
2.Certainly zero
3.Very likely zero
4.Very likely one
In which technique spot beam antennas are used to point the radio signals in different directions?
1.Code division
2.Space division
3.Frequency division
4.None of the mentioned
QAM is a combination of
1.ASK and FSK
2.ASK and PSK
3.PSK and FSK
4.None of the mentioned
QPSK amplitude modulates
1.Sine function
2.Cosine function
3.Sine & Cosine function
4.None of the mentioned
QPSK is a composite of
1.Two BPSK
2.Three BPSK
3.Two FSK
4.Two M-ary PSK
The bandwidth efficiency increases as M increases.
1.True
2.False
The bandwidth efficiency of MFSK is
1.M/log2M
2.log2M/M
3.M/log10M
4.log10M/M
The bandwidth efficiency of QFSK is _______ that of BFSK.
1.Greater than
2.Less than
3.Equal to
4.None of the mentioned
The capacity relationship is given by
1.C = W log2 ( 1+S/N )
2.C = 2W log2 ( 1+S/N )
3.C = W log2 ( 1-S/N )
4.C = W log10 ( 1+S/N )
The IF transmission bandwidth of MFSK is
1.M/T
2.T/M
3.2M/T
4.M/2
The inter leaver connected between the two decoders is used to
1.Remove error bursts
2.Scatter error bursts
3.Add error bursts
4.None of the mentioned
The minimum nyquist bandwidth needed for baseband transmission of Rs symbols per second is
1.Rs
2.2Rs
3.Rs/2
4.Rs2
The mixing and filtering of DSB removes
1.LSB
2.USB
3.LSB & USB
4.None of the mentioned
The orbital period of communication satellites is _______ as that of earth’s rotational period.
1.Same
2.Greater
3.Lesser
4.None of the mentioned
The primary communication resource is
1.Transmitted power
2.Received power
3.Efficiency
4.None of the mentioned
The super group is made up of
1.Five groups
2.Sixty channels
3.Five groups & Sixty channels
4.None of the mentioned
The system will be more bandwidth efficient as WTb decreases.
1.True
2.False
The transmission rate is given as
1.R/log2M
2.log2M/R
3.R/log10M
4.log10M/R
Trellis coded modulation uses
1.Non binary method
2.Uses redundant bits
3.No expansion of bandwidth
4.All of the mentioned
Turbo code is a
1.Serial concatenation code
2.Parallel concatenation code
3.Block code
4. None of the mentioned
Turbo codes are
1.Forward error correction codes
2.Backward error correction codes
3.Error detection codes
4.None of the mentioned
Which modulation has lower side lobe levels?
1.QPSK
2.OQPSK
3.BPSK
4.MSK
Which modulation is selected for power limited system?
1.MPSK
2. MFSK
3.MPSK & MFSK
4. None of the mentioned
Which modulation is spectrally more efficient?
1.BPSK
2.MSK
3.QPSK
4.OQPSK
Which modulation is the most efficient one?
1.BPSK
2.BFSK
3. QPSK
4.QAM
Which modulation requires more bandwidth?
1.QPSK
2.OQPSK
3.BPSK
4.BFSK
Which modulation scheme uses nonlinear transponders?
1.MSK
2.Offset QPSK
3.MSK & Offset QPSK
4.None of the mentioned
Which modulation spectrum has narrow main lobe?
1.QPSK
2.OQPSK
3.BPSK
4.MSK
Which parameter is called as Shannon limit?
1.PB/N0
2.EB/N0
3.EBN0
4. None of the mentioned
Which refers to the presence of error correction coding scheme?
1.Coded
2.Uncoded
3.Coded & Uncoded
4.None of the mentioned
Which technique can be used for bandwidth reduction?
1.BPSK
2.QPSK
3.MPSK
4.MFSK