Summary

This section presents an overview of the mandatory and desirable recommendations that need to be fulfilled by a CORS to join the IGS network. They are intended to be applicable both to current active IGS stations and to proposed stations. Full compliance with these Guidelines is clearly desired by the IGS, however where guidelines cannot be complied with, station operators are asked to consult with the Infrastructure Committee. Detailed information about the shown recommendations can be found in subsequent chapters of these Guidelines.

Legend

This feature is the minimum required one.

This feature is encouraged but not mandatory.

This feature is not recommended.

General

Recommendation	Classification
Station belongs to a national/regional geodetic network1
Station planned and installed for continuous and permanent operation
Station’s operating agency maintains full capability to repair, upgrade and maintain the station

Foundation and Location

Recommendation	Classification
Bedrock or massive concrete base
Mounted on buildings or similar structures2
Clear sky view with limited obstructions above 10°
Site is clear from signal obstructions or RFI
Site is clear from reflective material

Monumentation and Mounting

Recommendation	Classification
Concrete pillar or braced (tri-, quad-, ...)pod monuments
(Steel) mounts attached to building
The mount locks the antenna in place to maintain orientation and level
The mount allows the antenna to be removed and returned within 0.5 mm and 1° of its original location and orientation

Power and Communication

Recommendation	Classification
Ensure continuous operation of all communication devices
Ensure remotely controlled access to the receiver

Receiver

Recommendation	Classification
Multi-frequency code and carrier phase tracking for all GNSS3
Continuous logging of raw GNSS data
Real-Time data streaming (RTCM)
All-in-view satellite tracking (healthy and unhealthy) with a minimum of 5° elevation (0° is encouraged)
Disabling pseudorange and phase smoothing
Disabling multipath mitigation
Ability to store a reasonable amount of raw data (depending on local circumstances)

Antenna

Recommendation	Classification
Use of an antenna with an IGS calibrated absolute antenna phase centre (mean calibration) as included in the official IGS ANTEX
Individually calibrated absolute antenna phase centre
Antenna levelled and oriented within 5° to true North
Antenna radome protection

Data

Recommendation	Classification
Data must be provided in RINEX format4
^^ Real-Time stream is available5:^^ RTCM 3 MSM5 stream for real-time applications6
Data must be resubmitted to the data centres after communication outage
RINEX data must be generated on-board the receiver or from native binary file
File completeness target	99%

High-rate RINEX files

Recommendation		Classification
Provision
Latency	< 5 minutes
Sampling rate	1 Hz
Duration	15 minutes

Hourly RINEX files

Recommendation		Classification
Provision
Latency	< 5 minutes
Sampling rate	30 seconds

Daily RINEX files

Recommendation		Classification
Provision
Latency	< 30 minutes
Sampling rate	30 seconds

Metadata

Recommendation	Classification
Complete and up-to-date metadata in IGS site log/GeodesyML format
Unique nine-character station identifier approved by IGS
Assigned with unique IERS DOMES number
Update of IGS site log within 24 hours of applied station change(s)
RINEX header matches the information in the IGS metadata record
Provision of pictures of the antenna installation in the 4 cardinal directions (N, E, S, W)

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1. Mandatory for regional CORS in the footprint of APREF, EPN, and SIRGAS. ↩

2. Waivers may be granted after revision by the SPC. ↩

3. New stations shall track all available frequency code and carrier phases. ↩

4. For new stations: RINEX 3.04 is the minimum accepted version. RINEX 2.11 is not accepted. ↩

5. New stations are highly encouraged to provide real-time streams. ↩

6. MSM7 is encouraged. ↩