FREQUENCY
2–18 GHz
TYP. PEAK GAIN
4 dBic
TYP. AXIAL RATIO
≤ 2.5 dB
POLARIZATION
RHCP / LHCP
Compact & lightweight
2.5 × 2.5 × 1.0 in and 4 oz (115 g).
Measured test report
VSWR and boresight axial ratio documented per unit.
Designed in the USA
Designed, assembled, and tested in California.
Product Details
The SPIR2000 is a cavity-backed spiral antenna that delivers circular polarization continuously from 2 to 18 GHz, a 9:1 bandwidth, from a single compact aperture. Its unidirectional pattern and low boresight axial ratio make it well suited to wideband direction finding, signal monitoring, and electromagnetic compatibility work where polarization sense matters. Each antenna is built around a PCB spiral element in an anodized-aluminum cavity and is offered in right-hand or left-hand circular polarization.
- Suited to wideband direction finding, electronic support measures (ESM) and signals intelligence, signal monitoring, EMC radiated testing, and circularly polarized antenna measurement.
- Cavity-backed spiral design produces a unidirectional radiation pattern and frequency-independent operation across the full 2 to 18 GHz range.
- Offered in right-hand (SPIR2000-R) or left-hand (SPIR2000-L) circular polarization; choose the sense when ordering.
- Low boresight axial ratio across the band gives clean circular polarization and strong rejection of the opposite-hand sense.
- Each unit ships with a measured test report of VSWR and boresight axial ratio; raw data (.txt/.csv) and custom characterization available on request.
Specifications
General
| Design | Cavity-backed spiral |
| Polarization | Circular (RHCP or LHCP) |
| Connector | SMA female |
| Impedance | 50 Ω |
| Maximum input power | 10 W |
| Construction | Anodized aluminum cavity with PCB spiral |
| Mounting | #10-24 threaded holes |
| Dimensions (L × W × H) | 63.5 × 63.5 × 25.4 mm (2.5 × 2.5 × 1.0 in) |
| Weight | 115 g (4 oz) |
Performance
| PARAMETER | FREQUENCY | MIN | TYP | MAX | UNIT |
|---|---|---|---|---|---|
| VSWR | 2.0 – 3.0 GHz | – | 1.8 | 2.5 | – |
| 3.0 – 13.0 GHz | – | 1.5 | 2.3 | ||
| 13.0 – 18.0 GHz | – | 1.8 | 2.8 | ||
| Gain | 2.0 – 3.0 GHz | -7.0 | -2.5 | 2.0 | dBic |
| 3.0 – 4.0 GHz | -2.0 | 1.0 | 4.0 | ||
| 4.0 – 18.0 GHz | 0.0 | 4.0 | 7.5 | ||
| Axial ratio | 2.0 – 3.0 GHz | 1.5 | 2.5 | 3.9 | dB |
| 3.0 – 16.0 GHz | 0.2 | 1.0 | 3.0 | ||
| 16.0 – 18.0 GHz | 0.8 | 2.0 | 3.6 | ||
| HPBW | 2.0 – 18.0 GHz | 55 | 80 | 120 | deg |
Specifications are typical and subject to change without notice. Height excludes the SMA connector; axial ratio is specified at boresight. Each unit ships with a measured test report.
