Shortwave frequencies refer to a range of radio frequencies that fall within the shortwave portion of the electromagnetic spectrum. Shortwave radio signals have wavelengths that are shorter than those of standard AM (Amplitude Modulation) radio waves but longer than those of FM (Frequency Modulation) radio waves. The shortwave frequency bands are widely used for international broadcasting and long-distance communication.
Shortwave frequencies typically cover the range from about 1.8 MHz (megahertz) to 30 MHz. Within this range, there are several frequency bands designated for different purposes, such as broadcasting, amateur radio, aviation, and maritime communication. These bands are divided into specific segments to accommodate various users and applications.
The shortwave frequency bands include:
- 25-Meter Band: Frequencies in the 11.6 to 12.1 MHz range.
- 31-Meter Band: Frequencies in the 9.4 to 10.0 MHz range.
- 41-Meter Band: Frequencies in the 7.2 to 7.6 MHz range.
- 49-Meter Band: Frequencies in the 5.9 to 6.2 MHz range.
- 60-Meter Band: Frequencies in the 4.75 to 5.06 MHz range.
- 75-Meter Band: Frequencies in the 3.9 to 4.0 MHz range.
- 90-Meter Band: Frequencies in the 3.2 to 3.4 MHz range.
- 120-Meter Band: Frequencies in the 2.3 to 2.495 MHz range.
These bands are allocated by international agreements, and the specific frequencies within each band can vary based on regional regulations. Shortwave frequencies are used for a variety of purposes, including:
- International broadcasting by radio stations to reach global audiences.
- Amateur (ham) radio operators communicating over long distances.
- Aviation and maritime communication.
- Emergency and disaster communications.
- Cultural and religious broadcasts to specific regions.
Shortwave radio signals have the advantage of being able to travel long distances due to their ability to reflect off the ionosphere, allowing them to reach beyond the line of sight. However, the quality of shortwave signals can vary based on factors like atmospheric conditions, time of day, and solar activity. Despite technological advancements, shortwave broadcasting remains relevant in certain contexts, especially in regions with limited communication infrastructure.
Key terms in plain language
Open a term for a concise explanation of language used on this page.
VoIP
Voice over Internet Protocol carries phone calls over an IP network instead of a traditional analog phone line. Call quality depends on network stability, latency, and traffic management.
Unified Communications (UCaaS)
A cloud-based combination of business calling, messaging, meetings, presence, and collaboration tools managed as one communications service.
SIP Trunking
A service that connects a business phone system to the public telephone network using Internet Protocol, replacing or supplementing traditional phone lines.
Bandwidth
The amount of data a connection can carry in a given time, usually measured in Mbps or Gbps. More bandwidth supports more users, devices, and simultaneous applications.
Latency
The time it takes data to travel between two points. Lower latency improves voice, video meetings, cloud applications, gaming, and other real-time services.
Service-Level Agreement (SLA)
A provider’s written commitment covering service targets such as availability, response time, repair time, and sometimes financial credits when commitments are missed.