Question

**Is that possible, for any antenna, to be used as a
receiver and transmitter? What is the point of that?**

Answer #1

A
WiFi receiver is connected to its antenna by a piece of cable 5cm
long. Considering that the receiver is tuned to 2.4GHz, can you say
that the instantaneous currents at the input of the receiver and at
the antenna terminals are equal? If not, for what approximate cable
lengths would they be equal?

Consider the Voyager spacecraft, transmit frequency 8.4 GHz,
transmitter power PT= 21.3 W, transmitting antenna gain
GT is 6.5 x 104 W/W at a distance of 6.8 x
1011m from Jupiter to Earth. Both the Voyager and earth
based antennas are parabolic dishes whose cross sectional area can
be assumed equal to the effective antenna aperture.
a) Calculate the Voyager antenna gain (dB) and diameter
b) Calculate the receiver antenna gain (dB) with a dish diameter
of 64m.
c) Calculate...

A radio transmitter is connected to an antenna having an
impedance 80 + j40 ohm with a 50 ohmcoaxial cable having a length
of 2.0 m. The impedance of the
transmitter is 50 ohm . The phase velocity of the signal
propagation in the coaxial cable is 2.0*108 m/s, and the
frequency of the sinusoidal signal is 800 MHz.
Find the following quantities:
a) The propagation constant of the signal in the cable.
b) The reflection coefficient at the antenna....

5.5) A 1.8 GHz transmitter and a receiver are separated by 6 km.
A sharp edge absorbing screen is inserted below and normal to the
direct path between transmitter and receiver, which is 2 km from
the transmitter. How closely can the edge of the screen approach
the direct path and not introduce excess path loss? 5.6) If in the
communication system described in Problem 5.5, the screen is
inserted so that its edge is 20 m above the direct...

Find the received power in watts if transmitted power is 1 watt,
recieve and transmit antenna gains each 1 dB, distance between
receiver and transmitter is 3 meters, and wavelength 30 cm. Assume
Pi = 3.

The broadcast transmitter transmits a sinusoidal radio signal at
a frequency of 95 MHz with a transmission power of 55 kW. The radio
signal is received at a distance of 2.5 km with a circular wire
antenna with a diameter of 18 cm. What is the maximum possible
electromotive force induced in the loop antenna, assuming that the
transmitted power is evenly distributed in all directions? Far from
the transmitter, the wave can be locally modeled as a planar wave....

22 gauge copper wire has 22 milli-? per foot resistance. If the
receiver loads the signal wire with 50? (for noise reduction) and
the transmitter applies a 2.5 V signal as a logic ‘1’, how many
feet of wire can be used between transmitter and receiver before
the logic ‘1’ becomes less than the 1.3 V minimum threshold for a
‘1’ at the receiver? Remember that voltage is being dropped in both
wires of the twisted pair.

An
earth station receiver has an effective noise temperature at its
input (call it point A) equal 30K. If an antenna of effective
temperature of 50K is connected to the receiver via a lossy
waveguide. Find the noise temperature at the point A (in K unit),
if the wave guide has a loss of 2.5 dB. Consider T(0) = 290K.

Design a half-wave length wire dipole antenna to be used as an
external antenna of a 5G router. (Imagine that the 5G system
operates at 28 GHz).

A fiber optic receiver has a sensitivity of -38 dBm. This is the
optical power required to operate with the desired mesage quality.
The transmitter produces a power level of 4 dBm. What are
the allowed system losses in dB? These losses are caused
by inefficient coupling from the transmitter into the fiber, by
connector and splice losses, and by losses in the fiber itself.

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 4 minutes ago

asked 18 minutes ago

asked 21 minutes ago

asked 21 minutes ago

asked 33 minutes ago

asked 33 minutes ago

asked 35 minutes ago

asked 35 minutes ago

asked 54 minutes ago

asked 55 minutes ago

asked 1 hour ago

asked 1 hour ago