Piksi® Multi (firmware v1.1 and newer) accepts RTK base station data input in widely available RTCM format.
The RTCM message details can be obtained from RTCM organization site: http://www.rtcm.org/
RTCM messages can be delivered to the receiver via any available interface (UART, Ethernet, USB) or received by the built-in NTRIP Client when Piksi Multi is connected to the Internet via Ethernet interface.
Supported RTCM Messages
Piksi Multi accepts RTCM v3.x messages listed below. As of firmware v2.0, Piksi Multi is capable of receiving RTCM v3.2 Multiple Signal Messages MSM4 to MSM7 which are necessary for differential operation with BeiDou and Galileo constellations, but also available for GPS and GLONASS.
(Piksi Multi firmware version supporting given message is provided in brackets)
RTCM v3.1 messages:
1002 - GPS L1 observations
1004 - GPS L1 and L2 observations
1005 - Stationary RTK reference station ARP
1006 - Stationary RTK reference station ARP with antenna height
1010 - GLONASS L1 observations (v1.2 and newer)
1012 - GLONASS L1 and L2 observations (v1.2 and newer)
1033 - Receiver and antenna descriptors (v1.4 and newer)
RTCM v3.2 messages:
1074 - GPS pseudorange, phase range & CNR observables (v2.0 and newer)
1075 - GPS pseudorange, phase range, Doppler, & CNR observables (v2.0 and newer)
1076 - GPS pseudorange, phase range & CNR observables (high resolution) (v2.0 and newer)
1077 - GPS pseudorange, phase range Doppler, & CNR observables (high resolution) (v2.0 and newer)
1084 - GLONASS pseudorange, phase range & CNR observables (v2.0 and newer)
1085 - GLONASS pseudorange, phase range, Doppler, & CNR observables (v2.0 and newer)
1086 - GLONASS pseudorange, phase range & CNR observables (high resolution) (v2.0 and newer)
1087 - GLONASS pseudorange, phase range Doppler, & CNR observables (high resolution) (v2.0 and newer)
1094 - Galileo pseudorange, phase range & CNR observables (v2.0 and newer)
1095 - Galileo pseudorange, phase range, Doppler, & CNR observables (v2.0 and newer)
1096 - Galileo pseudorange, phase range & CNR observables (high resolution) (v2.0 and newer)
1097 - Galileo pseudorange, phase range Doppler, & CNR observables (high resolution) (v2.0 and newer)
1124 - BeiDou pseudorange, phase range & CNR observables (v2.0 and newer)
1125 - BeiDou pseudorange, phase range, Doppler, & CNR observables (v2.0 and newer)
1126 - BeiDou pseudorange, phase range & CNR observables (high resolution) (v2.0 and newer)
1127 - BeiDou pseudorange, phase range Doppler, & CNR observables (high resolution) (v2.0 and newer)
1230 - GLONASS L1 and L2 code-phase biases (v1.4 and newer)
Notes:
- For the best performance use base stations that output messages 1004 and 1012, or MSM7.
- Starting from firmware v1.5 GPS L2 observations are required from base for rover to converge to RTK fixed solution. Without L2 data receiver will stay in RTK float mode.
- In order to use GLONASS for RTK positioning, either message 1033 or 1230 is required. Message 1230 is used in priority, but if unavailable the receiver will use the message 1033 to determine hardware biases necessary for GLONASS RTK.
Direct RTCM v3 Input
To enable direct RTCM v3 input change desired port mode to RTCMv3 IN using Swift Console (Settings tab -> desired interface port group -> mode). To make change permanent click Save to Device button on the Swift Console.
Figure 1. Example of RTCMv3 input enabled on UART0