User's Manual

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The pilot beacon generator facilitates E911 and other location based services (LBS) for in building and/or DAS based installations of
CDMA2000/1xEV-DO cellular networks. In these situations the normal methods based for location determination, direct reception of GPS
by the mobile station or triangulation using the signals from multiple base stations, do not work. Signals from the GPS system are
sufficiently weak that even if the mobile station’s GPS receiver might ultimately be able to lock on to the satellites, the acquisition time will be
too long. And since indoor service is typically provided either by a single strong local cell or by using a repeater, there aren’t multiple
signals on which to triangulate while DAS based deployments result in too many signals with indeterminate timing. By placing a pilot signal
at a known PN offset the LBS algorithm can quickly and reliably be made aware that it is within a specific building or other location where
normal location determining solutions are ineffective. This information can be used to aid the GPS receiver in acquiring signals if they are
present or be used as a position report directly until more accurate information becomes available.
3GPP2 The standards body comprised of representatives of interested companies that is responsible for the
development and maintenance of the operational standards for the CDMA2000 system. Http://
www.3gpp2.org
AGC Automatic Gain Control
CDMA Code Division (or, Domain) Multiple Access: The general term for the technology used in the CDMA2000
system as well as others. Also a shorthand reference to the CDMA2000 system and its derivatives
such as 1xEV-DO
Chip A single element, a ‘1’ or a ‘0’, of the PN Sequence in a CDMA system. The chip rate for the CDMA2000
system is 1.2288 Mchips/second.
CSI Cellular Specialties Incorporated
DAS Distributed Antenna System
ERP Effective Radiated Power
EST Even Second Tick: In the CDMA2000 cellular system all time values are referenced to the start of the
even seconds of time as indicated by GPS.
FCC Federal Communications Commission
FPGA Field Programmable Gate Array
GPS Global Positioning System
IF Intermediate Frequency
LED Light Emitting Diode
NEMA National Electrical Manufacturers Association
PA Power Amplifier
PN Pseudo random Number: A number chosen by some algorithm that approximates a random process.
Can be short for “PN Sequence”, “PN Number”, or “PN Offset” when discussing the CDMA2000
system.
PN Number In the CDMA2000 system only a subset of the possible PN Offsets are used for base station
identification. Each of these allowed offsets is given a unique number from 0 to 511.
PN Offset In the CDMA2000 System each base station is identified by the offset in time from the EST at which the
start of the Pilot PN Sequence occurs. The offset is specified in terms of number of chips.
PN Sequence A sequence of pseudo random numbers. In the CDMA2000 system several such sequences are used.
The one relevant to ICEBreaker is the Pilot, or Short, sequence which is a 2
15
element long sequence of
ones and zeros.
PPS Pulse per Second: Refers the pulse repetition rate of the timing signal used as a time reference.
RF Radio Frequency
SBC Single Board Computer
Tau Timing Offset or Delay Adjustment: In the CDMA2000 system the timing of the downlink signal is
required to be aligned with the EST as it is transmitted from the antenna. Tau allows the timing of the
internal PN Sequence to be adjusted to compensate for the delays of the base station hardware such
that the timing will be correct at the antenna
USB Universal Serial Bus
Acronyms and Definitions:
Product Introduction: