SBAS message configuration

In the Settings Browser, select Scenario Generator. Click the SBAS message cell, and use the dialog box button to launch the SBAS message configuration dialog box.

The following table lists all the supported SBAS Message Types and their contents.

To configure each message type, refer to the "How to Configure" column. For Message Type 9 and Message Type 17, refer to SBAS Ephemeris File (Optional) and SBAS Almanac File.

SBAS Message Type	Contents	How to configure
MT 1	PRN Mask assignments, set up to 51 of 210 bits	Refer to MT 1
MT 2 to 5	Fast corrections	Refer to MT 2 to 5
MT 7	Fast Correction Degradation factor	Refer to MT 7
MT 9	9 GEO navigation message (X, Y, Z, time, etc.)	SBAS Ephemeris File (Optional)
MT 12	WAAS Network Time/UTC offset parameters	Refer to MT 12
MT 17	GEO almanacs message	SBAS Almanac File
MT 18	Lonospheric grid point masks	Refer to MT 18
MT 25	Long term satellite error corrections	Refer to MT 25
MT 26	Ionospheric delay corrections	Refer to MT 26

MT 1

To configure Closed message type 1, click MT 1 node.

Coupling: Message type 1 (PRN Mask) indicates which PRNs are included in some other types. Therefore,when type 1 mask gets changed, each enabled satellite in the mask will have a corresponding row under MT 2 to 5, MT 7 and MT 25.

IODP

Choice: 0 to 3

Default: 0

2-bit issue of data PRN (IODP) to indicate the mask’s applicability to the corrections and accuracies contained in messages to which the mask applies.

Mask

The PRN mask is consisted of 210 ordered slots.Each slot indicates if data is provided for the corresponding satellite, defined in the following Table.

PRN	Assignment
1-37	GPS/GPS Reserved
38-61	GLONASS
62-119	Future GNSS
120-138	SBAS
139-210	Future GEO

N7609B provides easy-to-configure buttons with the index from 1 to 210, representing each PRN Slot. Enable a particular satellite in the PRN mask by highlighting the corresponding button in green.

SBAS	PRN
WAAS	133,135,138
EGNOS	120,124,126
MSAS	129,137
GAGAN	127,128
Reserved	121,122, 123,125,130,131,132,134,136

Couplings:

MT 2 to 5

To configure Closed message type 2 to 5, click MT 2 to 5 node.

IODP

Choice: 0 to 3

Default: 0

2-bit issue of data PRN (IODP) to indicate the mask’s applicability to the corrections and accuracies contained in messages to which the mask applies.

IODF

Issue of data for fast correction.

FC(m)

Fast correction

[-255.875 ~ 255.875]. Fast correction in meters to be applied to measured pseudorange.

UDREI

[0 ~ 15] Indicator of User range error

MT 7

To configure Closed message type 7, click MT 7 node .

IODP

Choice: 0 to 3

Default: 0

2-bit issue of data PRN (IODP) to indicate the mask’s applicability to the corrections and accuracies contained in messages to which the mask applies.

System Latency

Choice: 0 to 15

Default: 0

System latency time.

ai

Choice: 0 to 15

Default: 0

Indicates degradation factor.

MT 12

To configure Closed message type 12, click MT 12 node.

Coupling: Click message type 12 to update delta_t_LS, WN_LSF, DN, delta_t_LSF according to the user leap seconds list. WNt and tot are updated to the nearest valid values of Start Date Time.

A1_SNT

[-7.45e-9 ~ 7.45e-9]

rate of time change between SNT and UTC

A0_SNT

[-1 ~ 1]

Time gap between SNT and UTC.

tot

[0 ~ 602112]

Time of applicability.

WNt

[0 ~ 255]

Week number of applicability.

Delat_t_LS

[-127 ~ 127]

Current leap seconds, read-only.

WN_LSF

[0 ~ 255]

Week number for future leap second, read-only

DN [1 ~ 7]

Day number for future leap second, read-only

Delta_t_LSF

[-127 ~ 127]

Future leap seconds, read-only.

UTC STD ID

[0 ~ 3]

UTC standard identifiers.

MT 18

To configure Closed message type 18, click MT 18 node.

Coupling:Message type 18 (IGP Mask) indicates which IGPs are included in MT 26 (ionosphere correction). Therefore, when type 18 mask changes, block list under Type 26 will be rebuilt based on the new mask.

Band Number

[0 ~ 8]

Band number of IGP, defined in WAAS spec 4.4.9.

IGP Mask

Enable one or more IGPs in the IGP mask by highlighting the corresponding button in green.

IODI

Issue of data for IGP mask.

MT 25

To configure Closed message type 25, click MT 25 node .

Coupling: d_x_rate, d_y_rate, d_z_rate and d_af1 are only visible when Velocity Code is 1.

Velocity Code

[ 0 | 1]

Velocity code indicates whether or not this half-message includes clock drift and velocity component error estimates.

PRN Mask No.

[0 ~ 51]

Sequence number of the bits set in the 210 bit mask.PRN Mask assignments is set up to 51 of 210 bits.

PRN

Display the PRN of the satellite.

IOD

[0 ~ 255]

Issue of ephemeris data for GPS

d_x, d_y, d_z

[-128 ~ 128]

Delta to calculated location in {x, y, z} axis

d_x_rate, d_y_rate, d_z_rate

[-0.625 ~ 0.625]

Rate of delta to calculated location in {x, y, z} axis

d_af0

[-2^21 ~ 2^21]

Delta of time gap to SNT

d_af1

[-2^32 ~ 2^32]

Rate of delta of time gap to SNT

IODP

[0 ~ 3]

Issue of data for PRN mask.

MT 26

To configure Closed message type 26, click MT 26 node .

Coupling:Message type 18 (IGP Mask) indicates which IGPs are included in MT 26 (ionosphere correction). Therefore, when type 18 mask changes, block list under Type 26 will be rebuilt based on the new mask.

Band Number

[0 ~ 8]

Band number of IGP, defined in WAAS spec 4.4.9.

Block ID

[0 ~ 13]

Block ID in the specified IGP band.

IODI Issue of data for IGP mask

Vertical Delay Estimation

[0 ~ 63.875]

The estimation of vertical delay for a specified IGP.

GIVEI

[0 ~ 15]

Grid Ionospheric Vertical Error Indicator.