Introduction

YGOR provides several parameters which together constitute the switching signals. These parameters are:

switching_signals_master

The Switching Signals Master selects which back-end provides the switching signals to all of the back-ends.

cal_state

Each element of the Cal State array specifies the state of the receiver calibration signal in the switching phase. The size of the array depends on the number of phases selected.

sig_ref_state

Each element of the SigRef array specifies the state of the frequency/load/beam (sky signal or reference) in the switching phase. The size of the array depends on the number of phases selected.

blanking_time

Each element of the Blanking array specifies the time in seconds at the beginning of each switch phase when data integration is inhibited. The size of the array depends on the number of phases selected.

number_of_phases

The Number of Phases specifies how many phases are in the switching cycle. This parameter can have any integer value between 1 and 10.

switch_period

The Switch Period specifies the time in seconds of a full switch cycle, i.e. switching once through the number of phases specified.

phase_start

Each element of the Phase Start array specifies the beginning of this phase as a fraction of the total switch cycle. The first start time must be zero, they must increase monotonically, and the last phase start time must be less than one. The effective integration time for a phase in one switching cycle is the product of the Switch Period and the difference between that phase's and the next phase's start times minus the Blanking Time. The size of the array depends on the number of phases selected.

AdvanceTime

In the DCR, two of the six switching signals may be advanced in time and sent to separate TTL output ports. These might be used to drive a high-inertia device, such as a secondary or tertiary mirror, to start it moving before the DCR switches phase integrators. The Advance Time specifies the time lead, in seconds between 0 and 0.5, of both of these signals.

AdvanceSig1

In the DCR, the Advance Sig1 parameter selects which of the six signals are advanced and connected to the first output port.

AdvanceSig2

In the DCR, the Advance Sig2 parameter selects which of the six signals are advanced and connected to the second output port.

switchDeltas

In the LO1, the switchDeltas parameter is an array of length 0 to 4 which contains the frequency switching offset values in MHz. Frequency switching advances through the switchDeltas array every time that sig_ref_state changes. switchDeltas is mapped into three GO Keywords: num_fsw_offsets, ref_freq_1, and ref_freq_2.

xferState

In the receivers, the xferState parameter controls whether or not beam switching is occurring. This parameter is mapped into the GO Keyword beam_ctrl.

calState

In the receivers, the calState parameter controls whether or not the receiver ``cal'' listens to external switching signals or to its own internal settings. This parameter is mapped into the GO Keyword cal_ctrl.

Furthermore, a GO Keyword, switch_mode, is defined within GO. The purpose of the switch_mode GO Keyword is to be able to set a majority of the switching signals into a known, pre-defined state by setting only one GO Keyword value.