u-blox ZED-F9P Integration Manual

ZED-F9P-Integration Manual
UBX-18010802 - R02

4 Receiver description Page 39 of 114
Advance Information
Figure 25: SPI Back-To-Back Read/Write Access
4.6 Multiple GNSS Assistance (MGA)
The u-blox MGA services provide a proprietary implementation of an A-GNSS protocol compatible
with u-blox GNSS receivers. When a client device makes an MGA assistance request, the service
responds with the requested data using UBX protocol messages. These messages are ready for
direct transmission to the receiver communication port without requiring any modification by the
client. Currently, these MGA services consist of AssistNow Online and Offline, each delivered by
the HTTP or HTTPS protocols. AssistNow Online optionally provides satellite ephemerides, health
information and time aiding data suitable for GNSS receiver systems with direct internet access.
The AssistNow Offline service benefits u-blox GNSS receivers that only have occasional internet
access. Users request data from the service by specifying the time period for which they want
coverage (1 to 5 weeks). The data downloaded from the service is organized by date and encoded
into a sequence of UBX MGA messages.
The ZED-F9P supports AssistNow Online.
4.6.1 AssistNow Online
AssistNow Online is u-blox' end-to-end Assisted GNSS (A-GNSS) solution for receivers that have
access to the Internet. Data supplied by the AssistNow Online Service can be directly uploaded to
a u-blox receiver in order to substantially reduce Time To First Fix (TTFF), even under poor signal
conditions. The system works by collecting data such as ephemeris and almanac from the satellites
through u-blox' Global Reference Network of receivers and providing this data to customers in a
convenient form that can be forwarded on directly to u-blox receivers.
The AssistNow Online Service uses a simple, stateless, HTTP interface. Therefore, it works on all
standard mobile communication networks that support Internet access, including GPRS, UMTS and
Wireless LAN. No special arrangements need to be made with mobile network operators to enable
AssistNow Online.

u-blox ZED-F9P Specifications

General

GNSS	GPS, GLONASS, Galileo, BeiDou, QZSS, SBAS
Concurrent GNSS	4
RTK	Yes
Velocity Accuracy	0.05 m/s
Time Pulse Accuracy	30 ns
Operating Temperature	-40°C to +85°C
Supply Voltage	2.7 V to 3.6 V
Channels	184
Frequency Bands	L1, L2
Dimensions	22 mm x 17 mm x 2.4 mm
Interfaces	UART, SPI, I2C