Precise (or Protected) code transmitted by GPS NavStar satellites. The code used (in addition to the C/A code) by very accurate survey and military GPS receivers.
An intermediate representation of a program that is file-format-independent and is executed by a virtual machine interpreter.
The Precise code. A very long sequence of pseudo random binary biphase modulations on the GPS carrier at a chip rate of 10.23 MHz which repeats about every 267 days. Each one week segment of this code is unique to one GPS satellite and is reset each week.
The precise code of the GPS signal typically used only by the U.S. military. It is encrypted and reset every seven days to prevent use from unauthorized persons.
The Y-code is the P-code encrypted to protect against spoofing and can only be accessed by authorized users.
"Precise" or "protected" code which is sent on both the L1 and L2 carrier frequencies. P-code has a 10.23MHz bit rate and a period of one week. Each satellite has a unique P-code that is used to distinguish the satellite from all other GPS satellites. (See Y-Code.)
The protected, or precise, code modulated on both L1 and L2 carrier signals. The P-code is a very long (about 1014 bits) sequence of pseudo-random binary biphase modulations on the GPS carrier at a chipping rate of 10.23 MHz which does not repeat itself for about 38 weeks. Each satellite uses a one-week segment of this code which is unique to each satellite, and reset each week.
Instructions for a mythical machine, known as a p-machine, are prepared by the language tools into "exceutable" form. A special program called an interpreter then emulates the p-machine by reading the p-codes one at a time, thereby executing the actions they imply. p-Code is very compact compared to native machine code - it also has the advantage of being portable between different CPU types (such as Motorola's and Intel's respective chip families).
Code that can't be directly understood and executed by the Windows operating system. In Visual Basic, code compiled to P-code is interpreted to native code at runtime. When you are creating an executable file, you can force Visual Basic to compile to P-code by setting the appropriate options in the Compile tab of the Project Properties dialog box.
A second signal sent by satellites over the L2 channel. This code is usually only used by the U.S. Military and is encrypted and reset every seven days to prevent use from unauthorized persons.