GPS Antenna for PX1122r

Choosing an antenna is based on the following characteristics:

• Size and weight limitations

• Cost

• Desired transmission distance

• Active Antennas

• Radio frequency

  • We need to use L1/L2 compatible antennas because that's what the PX112r supports.

  • L1: 1575.42 MHz, L2: 1227.60 MHz

• Constellation: GPS American, But PX1122R can provide all GNSS constellation support

• Connector: There are different connector types available depending on the antennas and sometimes they are not the same as the connector type on the receiver side. Need an adapter? The PX1122r has an RF input port

• Input Impedance for GPS PX1122r and antennas is 50ohm

• Voltage: The power supply that an antenna will accept is usually within a certain range. The receiver outputs 3.3V.

• Current Drawn: Need to make sure the receiver can provide the current ( PX1122R provides 50-60mA) which is above the necessary current drawn by antenna.

• Amplifier Gain (Performance): ratio of input to output power -

  • The gain of the antenna should be within the range of the receiver

    • Need to choose an antenna below with a gain below 40

    • Noise figure (degradesSignal to noise ratio) should be less than 2dB

    • A higher gain antenna provides better signal reception in areas with poor signal strength.

Open

• High-performance antennas are needed to achieve optimal performance

• Since we will mount the antennas on the drone, the target weight should be < 100g

• The header on the board is assumed to be SMA Female for now (https://discuss.ardupilot.org/t/50-skytraq-rtk-receiver-has-anyone-used-it/87555/34 )

1. Tallysman TW7872

Advantage: High Performance, Dual-frequency RTK systems, Precision GPS positioning

Disadvantage: Costly - 199$, Voltage and noise figure might not be supported

2. Tallysman TW3865/3867

Advantage: Ideal for dual frequency RTK, Great Multipath Rejection, Increased system accuracy

Cost: 194$

3. Taoglas AGPSF.36G

Advantage: Cheap solution that meets all relevant criteria, UAVs also listed as a typical application. Low noise figure and axial ratio as well as good out-of-band rejection.

Cost: 34.71USD

4. ANN-MB-00 ublox

Advantages: The ANN-MB series includes a high-performance multi-band RHCP dual-feed patch antenna element, a built-in high-gain LNA with SAW pre-filtering, and a 5 m antenna cable with three connector options (SMA, SMB, MCX).

Cost: 79.95$

5. TOP106 from TOPGNSS

Cost: 133.95$

6. SPK6618 GNSS Antenna

Advantages: The antenna has a high gain and wide beam pattern, which ensures a good receiving effect even for signals received at a low elevation.

A multi-feed design scheme is used to ensure the coincidence of phases and minimize the influence of the antenna on measurements.

Cost: 124.95$

7. TOPGNSS AN106 GNSS

Advantage: The antenna unit has high gain, good reception effect for low elevation satellite signals, and a sufficient number of satellites available for the system

Cost: 165$

8. Taoglas AA.175 - Going ahead with this one, there are two in the bay area!

Cost: 71.93 USD

40mm Al,Cu/Steel ground plane reqd since antenna is metal mounted

References:

https://support.sbg-systems.com/sc/kb/latest/technology-insights/antenna-characteristics-how-to-choose-the-correct-one#:~:text=It%20is%20important%20to%20use,GPS%20constellation%20which%20is%20limiting

https://firstsourcewireless.com/en-ca/blogs/blog/a-comprehensive-overview-of-gps-antennas#:~:text=GPS%20antennas%20typically%20have%20a,areas%20with%20poor%20signal%20strength.

https://novotech.com/learn/m2m-blog/blog/2021/11/15/ultimate-gps-antenna-knowledge-base/#:~:text=There%20are%20two%20major%20types,come%20with%20in-built%20antennas

PX1122r Datasheet:

https://docplayer.net/184925906-Px1122r-small-size-multi-band-gnss-receiver-for-centimeter-level-accuracy-applications-features-applications.html