Pseudobinary

Pseudobinary or 18-bit integer data format is used to transmit a signed or unsigned integer. The 18 bits are encoded across 3 bytes. When signed, the value is encoded using a two-complement representation. As an integer cannot directly represent a fractional number, measurements are often scaled before storing to the GOES data table. For example, a water-level surface elevation of 123.45 ft can be multiplied by 100 to get an integer of 12345. This integer is stored for transmission with the encoding shown in Example encoding of water level surface elevation value of 12345.

Example encoding of water level surface elevation value of 12345

Character 1 = C Character 2 = @ Character 3 = y

p

1

b18

b17

b16

b15

b14

b13

p

1

b12

b11

b10

b9

b8

b7

p

1

b6

b5

b4

b3

b2

b1

0 1 0 0 0 0 1 1 0 1 0 0 0 0 0 0 0 1 1 1 1 0 0 1