You are not logged in.
Hi.
I was wondering if there exists any beam switching antenna (or Switched Beam Antenna) that works with WARPv3? Thank you.
Regards,
Antony
Offline
I'm not familiar with any antennas which integrate beam switching. You will need to investigate this further.
Any RF equipment (cable, attenuator, antenna) with a 50-ohm SMA plug (male) connector will connect to the RF interfaces on WARP hardware.
Offline
murphpo wrote:
I'm not familiar with any antennas which integrate beam switching. You will need to investigate this further.
Any RF equipment (cable, attenuator, antenna) with a 50-ohm SMA plug (male) connector will connect to the RF interfaces on WARP hardware.
I see. So I would like to make the WARP control the beam of the beam-switching antenna. Do you think it is possible or not? I mean, could the SMA connector transmit anything other than data, such as beam control signal?
Thank you.
Offline
The SMA jack is connected to the MAX2829 Tx/Rx interfaces. There is no way to inject other signals into the signal at the SMA jack. You could use the WARP v3 debug header (16 bits of digital I/O) as a control interface to external hardware.
Offline
murphpo wrote:
The SMA jack is connected to the MAX2829 Tx/Rx interfaces. There is no way to inject other signals into the signal at the SMA jack. You could use the WARP v3 debug header (16 bits of digital I/O) as a control interface to external hardware.
Hi Patrick, first thank you for your prompt reply! I have a new (but hopefully simpler) question for you: since I couldn't find the beam-switching antenna I mentioned above, I have to build it myself. To start, I want to put two directional antennas together and turn on only 1 of them at a time. So do you think it is possible to do the following:
1. connecting 2 directional antennas to an RF switch like this http://www.testparts-store.com/hp-agile … rf-relay/, and connect the switch to WARP
2. use the debug header to control the switch so that only 1 antenna is working at a time
If it's feasible, can you give me some advice on which RF switch I should use? Thank you very much in advance!
Offline
Using an RF switch to connect one RF interface to many antennas is definitely feasible. There are lots of switch options. For example, Minicircuits has many RF switches that cover the 2.4 GHz band, like the ZSDR-230+. We've never used a switch like this, but have always had good experiences with Minicircuits parts.
A few parameters to consider:
-Impedance: the RF interfaces on WARP hardware are 50 ohm
-Max power: the max Tx power on WARP hardware is around 20 dBm. Make sure the switch can handle this much power. The max input power spec might be given as the "X dB compression" level, indicating the minimum input power at which the switch will compress the signal by X dB. Compression is bad, so a high compression level is better.
-Control interface: if you want to control the switch from the WARP node's FPGA you will need a switch with digital control inputs. To use the WARP v3 debug header the control signals must accept 2.5v logic. Technically the V_oh for a 2.5v Virtex-6 pin is 2.1v, but if you keep the digital control cables short you can probably use a switch with V_ih of 2.0v (like that Minicircuits switch) without any trouble.
-Isolation: no RF switch is perfect. Even when "off" the disabled interface will see some Tx power and contribute some Rx power. Higher isolation is better.
-Switching time: your application will determine how much switching time you can tolerate. My intuition is a mechanical switch will have higher isolation (good) but longer switching time (bad).
-Supply voltage: many switches require a constant power supply. I would suggest driving this with an external supply, not from the WARP v3 board.
Offline