Table 8. NI USRP-2921 Module Front Panel Connectors (Continued)
Connector
Use
REF IN
Input terminal for an external reference signal for the local oscillator
(LO) on the device. REF IN is an SMA (f) connector with an
impedance of 50 Ω and is a single-ended reference input. REF IN
accepts a 10 MHz signal with a minimum input power of 0 dBm
(.632 V
pk-pk
) and a maximum input power of 15 dBm (3.56 V
pk-pk
) for
a square wave or sine wave.
PPS IN
Input terminal for the pulse per second (PPS) timing reference.
PPS IN is an SMA (f) connector with an impedance of 50 Ω and is a
single-ended input. PPS IN accepts 0 V to 3.3 V TTL and 0 V to 5 V
TTL signals.
MIMO
EXPANSION
The MIMO EXPANSION interface port connects two NI USRP
devices using a compatible MIMO cable.
GB ETHERNET
The gigabit Ethernet port accepts an RJ-45 connector and gigabit
Ethernet compatible cable (Category 5, Category 5e, or Category 6).
POWER
The power input accepts a 6 V, 3 A external DC power connector.
Table 9. NI USRP-2921 Module LEDs
LED
Indication
A
Indicates the transmit status of the module:
OFF—The module is not transmitting data.
GREEN—The module is transmitting data.
B
Indicates the status of the physical MIMO cable link:
OFF—The modules are not connected using the MIMO cable.
GREEN—The modules are connected using the MIMO cable.
C
Indicates the receive status of the module:
OFF—The module is not receiving data.
GREEN—The module is receiving data.
D
Indicates the firmware status of the module:
OFF—The firmware is not loaded.
GREEN—The firmware is loaded.
NI USRP-29xx Getting Started Guide
|
© National Instruments
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