Telecoms
Point-to-Point Wireless Links: A Complete Guide
A point-to-point (PtP) wireless link connects two locations with a dedicated microwave radio link. It is the backbone of many Jamaican enterprise networks, providing high-speed connectivity where fiber is unavailable or too expensive to deploy.
How PtP wireless works
Two radios (transceivers) are installed at each end of the link, each with a directional antenna. One radio transmits while the other receives, and vice versa. The link operates in licensed or unlicensed frequency bands:
- Unlicensed (5 GHz, 6 GHz, 60 GHz) — no regulatory approval needed, faster to deploy, subject to interference
- Licensed (6 GHz, 11 GHz, 18 GHz, 23 GHz) — requires a license from the SMA, protected from interference, higher cost
For most Jamaican enterprise links under 10 km, unlicensed 5 GHz is sufficient. For critical links or longer distances, licensed bands provide reliability.
Line of sight
PtP wireless requires line of sight (LOS) between the two endpoints. This means:
- No buildings, trees, or terrain blocking the path
- Fresnel zone clearance — the elliptical zone around the visual path must be at least 60% clear
- Earth curvature matters for links over 10 km
A site survey with a path profile analysis is essential before deployment. "Looks clear" is not engineering.
Link budget
The link budget is the calculation of whether the link will work. It accounts for:
- Transmit power
- Antenna gain (both ends)
- Free space path loss (distance)
- Frequency
- Atmospheric attenuation (rain, humidity)
- Cable and connector losses
- Receiver sensitivity
The result is the fade margin — the buffer between the signal the receiver gets and the minimum it needs. A fade margin of 20 dB or more is recommended for reliable operation in Jamaica's rain environment.
Throughput
Modern PtP links deliver: - 5 GHz unlicensed: 100 Mbps to 1 Gbps (depending on channel width and technology) - 11 GHz licensed: 100 Mbps to 2 Gbps - 60 GHz (short range): 1-10 Gbps
Actual throughput depends on distance, channel width, modulation, and interference.
Deployment steps
- Path survey — confirm line of sight and Fresnel zone clearance
- Link budget calculation — confirm the link will work at the required reliability
- Frequency coordination — select a clean channel (or apply for a license)
- Installation — mount radios, align antennas, configure
- Alignment — fine-tune antenna alignment for maximum signal
- Testing — verify throughput, latency, and stability under load
- Monitoring — set up SNMP monitoring for signal strength and uptime
Jamaica-specific considerations
- Rain attenuation — Jamaica's heavy rain attenuates microwave signals, especially at higher frequencies. Link budgets must account for rain fade.
- Hurricane resilience — mounts and antennas must withstand hurricane-force winds
- Lightning protection — every outdoor radio must have surge protection on power and data cables
- SMA licensing — licensed frequencies require Spectrum Management Authority approval
Common mistakes
- No path survey — deploying without confirming LOS leads to a link that does not work
- Insufficient fade margin — a link that works in dry weather fails in heavy rain
- No surge protection — lightning destroys unprotected radios
- Poor alignment — a few degrees of misalignment can halve throughput
- Wrong frequency — using 5 GHz in a congested area when licensed 11 GHz was needed
Next steps
If you need a PtP wireless link, request a path survey. We evaluate the sites, calculate the link budget, and deploy a link engineered for Jamaican conditions.