Overview: why communications choices matter for real projects
Choosing the right communications technology shapes range, power budget, latency and maintainability of every project - from a university sensor lab to a factory proof-of-concept. This guide focuses on practical selection for South African makers, students and procurement teams: how to decide between Wi-Fi, LoRa, BLE, wired Ethernet and simple RF links; how supply, lead times and branch pickup affect delivery; and how to spec parts so homework, prototypes and production runs work first time.
Common communications technologies and where we use them
- Wi-Fi (2.4 GHz / 5 GHz) - high throughput for cameras, gateways and development boards.
- LoRa / Sub-GHz - low-data, long-range telemetry (agriculture, remote sensors).
- Bluetooth Low Energy (BLE) - short range low-power peripherals, wearables, mobile pairing.
- Wired Ethernet / PoE - deterministic links for industrial or campus networks and power-over-data.
- Simple RF modules (433/868/915 MHz) - cost-effective telemetry and remote control.
Standards and practical constraints
Standards define radios and connectors but the right choice depends on local realities: stock availability at our Samrand head office and branches can shorten lead times; larger orders for labs may require a formal quote and VAT invoice. Browse product ranges to check compatibility and availability on the Communica site - start at the Collections page for category navigation.
Selection criteria: signal, power, range and ecosystem
1. Signal environment and antenna choices
In urban Cape Town or Johannesburg, interference can reduce effective range. Choose modules with removable antennas or U.FL connectors so you can swap to a directional antenna when needed. For indoor student labs, integrated PCB antennas simplify assembly; for outdoor or long-range links, favour SMA/RP-SMA connectors and evaluate gain (dBi) vs. size.
2. Power budget and duty cycle
Low-power radios (LoRa, BLE) let battery projects run months to years. For Wi-Fi projects, expect higher average current - plan battery capacity or use PoE. Use the formula below to estimate battery life for simple cases:
Battery life (hours) = Battery capacity (mAh) / Average current draw (mA)
Example: 2000 mAh battery, average 50 mA draw => 40 hours. For bursty radios, calculate average by duty cycle: Average = TxCurrent*TxTime + SleepCurrent*SleepTime (all over cycle time).
3. Throughput, latency and protocol stacks
Match protocol to application: real-time control prefers low-latency links (Wi-Fi/Ethernet), while sensor telemetry tolerates high latency but needs long range (LoRaWAN). For gateway designs, ensure MCU and radio firmware stacks are compatible - many Communica-stocked dev boards pair with ESP32, Raspberry Pi or LoRa concentrator modules. See brand choices on the communications supplier south africa page for module families commonly used in South African projects.
Quick spec comparison
| Technology | Typical Range | Typical Power | Use Cases |
|---|---|---|---|
| BLE | 10-50 m | Very low | Beacons, wearables |
| Wi-Fi | 30-200 m (AP-dependant) | High | Video, gateways |
| LoRa (sub-GHz) | 2-15 km (line-of-sight) | Low | Agriculture, remote sensors |
| Ethernet / PoE | 100 m (copper) | Powered | Industrial, cameras |
Use this table as a starting point - site surveys and antenna tests should validate final choices. For part availability and branch collection, check stock and collection options at our communications in stock south africa page to plan pickups from Samrand, Pretoria or Cape Town.
