P-Code
See Precision (P)-Code Packet
A unit of data that is routed between an origin and a destination on the Internet or any other packet-switched network. Palm Inc
Makes the Palm OS® and the line of Palm™ handheld devices and accessories. Palm, Inc. split from its parent company, 3Com, early in 2000. Palm OS®
The operating system used on Palm™ handhelds and other third-party devices. Parallel Channel Receiver
A continuous tracking receiver using multiple receiver circuits to track more than one satellite simultaneously. Parallel of latitude
An imaginary line circling the surface of the earth that is parallel to the equator; a line of latitude. Passive Matrix Display
A common LCD technology used in laptops. Passive matrix displays (DSTN, CSTN, etc.) are not quite as sharp and do not have as broad a viewing angle as active matrix (TFT) displays, but they have improved dramatically over the years. Looking head on into a passive matrix screen is not all that different than looking at an active matrix (TFT) screen. The difference is more noticeable with the viewing angle. A person looking from the side sees a dimmer image with passive matrix. Patch antenna
An antenna based on a plated section of metal on a circuit board and its associated electronics used for receiving GPS signals. PC Card
A PC Card is a credit card-size memory or I/O device that fits into a personal computer, usually a notebook or laptop computer. The PC Card is based on standards published by the Personal Computer Memory Card International Association (PCMCIA), an industry group organized in 1989 to promote standards for both memory and I/O integrated circuit cards. PCMCIA
See Personal Computer Memory Card International Association PDA
See Personal Digital Assistant PDOP
See Dilution of Precision Personal Computer Memory Card International Association (PCMCIA)
The PCMCIA (Personal Computer Memory Card International Association) is an industry group organized in 1989 to promote standards for a credit card-size memory or I/O device that would fit into a personal computer, usually a notebook or laptop computer. The PCMCIA 2.1 Standard was published in 1993. As a result, PC users can be assured of standard attachments for any peripheral device that follows the standard. The initial standard and its subsequent releases describe a standard product, the PC Card. Personal Digital Assistant (PDA)
A small mobile hand-held device that provides computing and information storage for personal or business use, often for keeping calendars and address information. Some PDAs are hand-held PC with small QWERTY keyboards. Another class of device uses a touch-screen and stylus for data entry. Phase Angle
The time difference between the same point on two different waves, usually measured in fractions of a cycle (radians or degrees). Phase Differencing
The technique of using different GPS receivers at different locations to measure the phase angles of the carrier signal from the same satellite. These angles are compared by a communications link between the two locations if real-time operations are required. Phase-Lock Loop
Another term for carrier-tracking loop. Pixel
The image displayed on monitors is made up lots of dots called pixels. Collectively, the number of pixels displayed is referred to as the image's resolution, the higher the resolution, the better the image will be. A pixel on a screen is a number of red, green, and blue phosphor dots. These dots are “excited” to varying degrees by the monitor's three electron guns, and the results mix additively to generate a specific colour. Platform
Refers to the group of hardware, software, and accessories that revolve around a particular operating system. See operating system. PNG
See Portable Network Graphics Pocket PC
Handheld operating system developed by Microsoft®, which also runs on third party devices.Pocket Word, Pocket Excel, Pocket Explorer, Pocket OutlookYou will notice a lot of Windows CE applications with the “pocket” designation. In general, this means that the application is a slimmed-down version of the desktop application you generally use. For example, Pocket Word has a similar look and feel to Microsoft Word; however, Pocket Word has fewer features to let it run in the smaller space provided by the Windows CE operating system. Point Positioning
Positions calculated by a single GPS receiver without reference to other receivers or known points. Position accuracy is typically 15 to 25 metres now that selective availability has been turned off. Port
A Port is part of the PC that is used for passing data in and out of a computing device. This is normally located on the back of the PC. The port can be a Serial Port - data is sent/received one bit at a time through a cable containing a single wire, or a Parallel port where the data is sent/received through a cable containing several pieces of wire so that more than one bit at a time can be processed. Also referred to as the I/O Port. Portable Network Graphics (PNG)
A file format for bitmapped graphic images approved by the World Wide Web Consortium as a replacement for GIF files. GIF files use a patented data compression algorithm; PNG is patent and licence free. Position
An exact, unique location based on a geographic coordinate system Position Dilution of Precision (PDOP)
See Dilution of Precision. Position error
The distance that the displayed position is off by. Position fixing
Using a coordinate system to determine a point on a map's location Position Fix
The GPS receiver's computed position coordinates. Position Format
The way in which the GPS receiver's position will be displayed on the screen. Commonly displayed as latitude/longitude in degrees and minutes, with options for degrees, minutes and seconds, degrees only, or one of several grid formats. Precise Positioning Service (PPS)
The full-accuracy, single-receiver GPS positioning service provided to the United States and its allied military organizations and other selected agencies. It is based on the dual-frequency P-Code and has resistance to jamming and spoofing. Precision (P)-Code
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. Prime Meridian
A line of longitude at 0 degrees that runs through Greenwich, England; used as the origin for measurements of longitude. PPS
See Precise Positioning Service PRN code
See Pseudorandom Noise (PRN) Code Pseudolite
A ground-based transmitter that mimics a GPS signal. These devices can be used around airports for such tasks as precision instrument landings. Pseudo-Random Code
The identifying signature signal transmitted by each GPS satellite and mirrored by the GPS receiver in order to separate and retrieve the signal from background noise. Pseudorandom Noise (PRN) Code
Two PRN codes are transmitted by GPS satellites: the C/A-code and P-code. Also called pseudonoise codes.
Each satellite transmits a unique C/A-Code and P-Code sequence (on the same L1 and L2 frequencies), and hence a satellite may be identified according to its "PRN number", e.g. PRN2 or PRN14 are particular GPS satellites. Pseudorange
The measured distance between the GPS receiver and the GPS satellite using uncorrected time comparisons from satellite-transmitted code and the local receiver's reference code. Psion
A British handheld computer company that makes its own hardware and operating system. Utilized by the Symbian device platform. |
