2.4.1.0 simulator.oldsetnoise

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simulator.oldsetnoise - Function

2.4.1 Set the noise level fixed sigma (mode=simplenoise) or Brown’s equation (mode=calculate) OBSOLETE VERSION

Description

Set various system parameters from which the thermal (ie, random additive) noise level will be calculated.

For mode=simplenoise, one specifies the standard deviation for the noise to be added to real and imaginary parts of the visibility.

For mode=calculate, the noise will vary with dish diameter, antenna efficiency, system temperature, opacity, sky temperature, etc. The noise will increase with the airmass if tau is greater than zero. The noise is calculated according to the Brown Equation (ie, R.L. Brown’s calculation of MMA sensitivity, 3Oct95):

√- 4-2[TrxeτA-+-Tatm-(eτA---ϵl)-+Tcmb]- ΔS = ϵqϵaπD2 √Δ-νΔt

(2.16)

Arguments


Inputs
mode	Mode of operation. String: ’simplenoise’—’calculate’
	allowed:	string
	Default:	calculate ’simplenoise’ ’calculate’
table	Name of noise table - not currently implemented
	allowed:	string
	Default:	”
simplenoise	Level of noise (if mode=simplenoise)
	allowed:	any
	Default:	variant 0.0Jy
antefficiency	antenna efficiency
	allowed:	double
	Default:	0.8 0.8
correfficiency	Correlation efficiency
	allowed:	double
	Default:	0.85 0.85
spillefficiency	Forward spillover efficiency
	allowed:	double
	Default:	0.85 0.85
tau	Atmospheric Opacity
	allowed:	double
	Default:	0.1 0.1
trx	Receiver temp (ie, all non-atmospheric Tsys contributions) [K]
	allowed:	double
	Default:	50 50
tatmos	(Physical, not Brightness) Temperature of atmosphere [K]
	allowed:	double
	Default:	230.0 230.0
tcmb	Temperature of cosmic microwave background [K]
	allowed:	double
	Default:	2.7 2.7

Returns
bool
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