diff --git a/tangostationcontrol/docs/source/devices/tilebeam-digitalbeam.rst b/tangostationcontrol/docs/source/devices/tilebeam-digitalbeam.rst index 6127918ec3567f0fc2fd52c15ee3b7a4780f5989..4089d082f4b5a62fd663673983ad03c8fa0f4710 100644 --- a/tangostationcontrol/docs/source/devices/tilebeam-digitalbeam.rst +++ b/tangostationcontrol/docs/source/devices/tilebeam-digitalbeam.rst @@ -7,7 +7,7 @@ Given a certain direction, and knowing the speed of light, one can compute the d In practice, antenna signals can only be coarsely delayed. Fine delay compensation consists of rotating the signal inputs to compensate for the remaining differences in phase. The amount of rotation is frequency dependent. The aligned signals are subsequently added, creating a single signal output of higher sensitivity towards the observed source, albeit with a narrower field of view. -Beam tracking therefor requires a *pointing* direction in which to observe, as well as the *positions* of the antennas involved. Finally, the antennas need to be periodically realigned to track moving sources. We distinguish the following concepts: +Beam tracking therefor requires a *pointing* direction in which to observe, as well as the *positions* of the antennas involved. Finally, the antennas need to be periodically realigned to track moving sources. We distinguish the following concepts: - *Beam forming* is combining individual element signals into one. This is performed by the HBAT hardware and SDP firmware, - *Beam steering* is uploading the delays or weights to the beam-forming hardware, in order to point the beam in a certain direction, @@ -15,7 +15,7 @@ Beam tracking therefor requires a *pointing* direction in which to observe, as w The ``tilebeam == DeviceProxy("STAT/TileBeam/1")`` device configures the HBA beam former in each HBA tile, which adds the signals of its 16 elements within the tile. The output signal of these tiles is used as input for the digital beam former (just like the direct output of an LBA). -The ``digitalbeam == DeviceProxy("STAT/DigitalBeam/1")`` device configures the digital beam formed in SDP from antenna or tile inputs. The output signal in SDP are *beamlets*, which can +The ``digitalbeam == DeviceProxy("STAT/DigitalBeam/1")`` device configures the digital beam formed in SDP from antenna or tile inputs. The output signal in SDP are *beamlets*, which can Both devices beamform the antennas configured in its associated ``AntennaField`` device, but differ in what they beamform and with respect to which position: