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The UPC-TestBed is composed by two main blocks: transmitter and receiver.
The two devices work on the 1800 MHz band at a 5MHz bandwidth.
On this figure the main block diagram of the system is depicted.
Transmitter
A complete scheme of the transmitter can be found here. It is compossed of:
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VME Rack: To allocate all VME cards.
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BIT-3: This card allows the communication between an external master (e.g. a PC) and the VME bus
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Pentek 4285: With two TMS320C40 processors. This card creates all the digital data and stores it in the memory card.
It is also the system master and controls all other devices. There is a photo of this board here.
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Memory card: Used to store all the digital signal.
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GPRIO-64: This is the D/A converter. It reads the data from the memory card, obtaining the I and Q baseband signals.
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Rubbidium clock: This clock is synchonized with the base station's one. It provides an accurate 10 MHz signal.
There is a photo here.
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Modulator: Conected with the outputs of the GPRIO-64 it modules the signal to the 1800 MHz band.
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Amplifier: To allow a long range communication.
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PC: To start and configure the system.
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GPS: To provide a reference location, in order to study the reliability of our system.
There is a photo of the transmitter mounted in a car here
Receiver
A function diagram of the receiver can be found here. It is compossed of:
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Antenna Array: Compossed of four antennas with lambda/2 separation between them. There's a photo
here.
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RF Header: Compossed of four independent RF receivers. One of the most important features of this system is the switch between
the external signal, from the antennas, and a calibration clock. This clock allows to calibrate all the system and
perform an I-Q and potence correction.
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VME Rack: To allocate all VME cards.
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BIT-3: This card allows the communication between an external master (e.g. a PC) and the VME bus
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Pentek 6606: This board receives the eight signals from the RF header (four I + four Q) and pass them by a
low pass filter to avoid aliasing artifacts. There is a photo of this board here.
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Pentek 6109: This is the A/D board. It has eight 10 MHz A/D. The output are four C40 comm ports, that allow a
high speed communication between boards. There is a photo here.
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Pentek 4285: With eight TMS320C40 processor. It receives the sampled signal and performs the calibration. This board
is the master of the system, and controls all the components. The calibrated data is transmitted to the 4291 board.
There is a photo of this board here.
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Pentek 4291: This is the digital processing core of the system. With four TMS320C6701 at 167 MHz., provides the outstanding
processing power of 4 Gigaflops. The calibrated signal is received from the 4285. All the digital processing, including channel estimation,
location algorithms, post-filtering, etc. are performed here.
There is a photo of this board here.
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GPS: To obtain a reference time, and compare the results with the mobile ones.
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Rubbidium clock: This clock is synchonized with the transmitter's one. It provides an accurate 10 MHz signal.
There is a photo here.
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