Configures an offset channel on one or both sides of carrier with center to center spacing as specified by the offset frequency and offset frequency definition. In case of multiple carriers, offset frequency is relative to the closest carrier.

Syntax

int32 __stdcall RFmxSpecAn_ACPCfgOffset(niRFmxInstrHandle instrumentHandle, char selectorString[], float64 offsetFrequency, int32 offsetSideband, int32 offsetEnabled)

Remarks

Use "offset<
<i>
n
</i>
>" as the selector string to configure this function.

Parameters

NameDirectionTypeDescription
instrumentHandle[in]niRFmxInstrHandle

This parameter specifies the RFmx session refnum. Instrument Handle In is obtained from the RFmxInstr_Initialize function.

selectorString[in]char[]

This parameter specifies the Selector String comprising of the signal name and offset number. If you do not specify the signal name, the default signal instance is used. The default value is "offset0".

Example:

"offset0"

"signal::sig1/offset0"

You can use the RFmxSpecAn_BuildOffsetString2 function to build the selector string.

offsetFrequency[in]float64

This parameter specifies the center or edge frequency, in Hz, of the offset channel, relative to the center frequency of the closest carrier as determined by the RFMXSPECAN_ATTR_ACP_OFFSET_FREQUENCY_DEFINITION attribute. The sign of offset frequency is ignored and the Offset Sideband parameter determines whether the upper, lower, or both offsets are measured. The default value is 1 MHz.

offsetSideband[in]int32

This parameter specifies whether the offset segment is present on one side, or on both sides of the carriers. The default value is Both.

Name

Value

Description

RFMXSPECAN_VAL_ACP_OFFSET_SIDEBAND_NEGATIVE

0 (0x0)

Configures a lower offset segment to the left of the leftmost carrier.

RFMXSPECAN_VAL_ACP_OFFSET_SIDEBAND_POSITIVE

1 (0x1)

Configures an upper offset segment to the right of the rightmost carrier.

RFMXSPECAN_VAL_ACP_OFFSET_SIDEBAND_BOTH

2 (0x2)

Configures both negative and positive offset segments.

offsetEnabled[in]int32

This parameter specifies whether to enable the offset channel for ACP measurement. The default value is True.

Name

Value

Description

RFMXSPECAN_VAL_ACP_OFFSET_FREQUENCY_ENABLED_FALSE

0 (0x0)

Disables the offset channel for ACP measurement.

RFMXSPECAN_VAL_ACP_OFFSET_FREQUENCY_ENABLED_TRUE

1 (0x1)

Enables the offset channel for ACP measurement.

Returns

Returns the status code of this operation. The status code either indicates success or describes an error or warning condition. Examine the status code from each call to an RFmx function to determine if an error has occurred.

To obtain a text description of the status code and additional information about the error condition, call the RFmxSpecAn_GetError function.

The general meaning of the status code is as follows:

Value

Meaning

0

Success

Positive Values

Warnings

Negative Values

Errors