RFSatellite Phone vs. Cell Phone: Key Differences Explained
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Cell phones and satellite phones are both widely used communication devices, but they differ significantly in terms of technology, connectivity, and application. Cell phones rely on terrestrial networks with limited coverage areas, while satellite phones use satellites to establish a direct connection from virtually anywhere on the planet. Understanding these differences is essential for choosing the right device based on location, purpose, and usage requirements. This article explores the key distinctions between satellite phones and cell phones, highlighting their respective advantages, disadvantages, and best use cases.
Satellite Phone: Based on Satellite Networks
A satellite phone, also known as a sat phone, is a mobile communication device that allows users to make or receive calls, send or receive text messages, and access data services via satellites orbiting around the Earth.
Satellite phones connect to a network of Low Earth Orbit (LEO) satellites. When a user initiates a call or sends a message, the signal is transmitted from the satellite phone to the nearest satellite overhead. The satellite receives the signal from the sat phone and transmits it to a ground station on Earth. The ground station functions as a gateway that routes the signal to the appropriate destination, such as another satellite phone, a landline phone, or a cell phone registered on a cellular network.
Image Alt Text: Iridium Satellite Operating Frequencies
Here are some features of satellite phones and their corresponding satellite network system:
- Network Usage: Satellite phones use satellite networks such as Iridium or Inmarsat to dial or receive calls.
- Typical Use Cases: They are mainly used in remote areas such as terrains, deserts, and polar regions, and for aviation and maritime communications.
- Cost: Satellite phones are generally very costly.
- Functionality: They are primarily used for voice and text messages. Internet services are planned for the future due to the launch of new satellites in the “Iridium NEXT” constellation. Dual-mode handsets provide both cellular (e.g., GSM) and satellite connectivity.
- Connectivity: Call drops due to handover are not an issue due to global coverage with one unique single number and SIM. This makes them a great option for frequent travelers on business trips. They are also used in maritime communication, defense, and disaster rescue operations.
- Service Provider Benefits: Currently, satellite phones don’t offer much benefit to service providers. However, with the launch and installation of Iridium NEXT satellites, more advanced features will be available. These will include aviation services, enabling airplanes to provide their location to earth stations or gateways, and internet services for maritime communication.
- Network Installation: Installation of a satellite network is complex and requires more resources and time. A satellite network consists of a satellite phone, 66 LEO satellites, and Earth stations or ground stations or gateways.
- Maintenance: Maintenance of a satellite system is complex and more costly.
- Ease of Use: It will take time for satellite phones to be used by more people, as it requires learning or familiarity with the workings of the satellite system. Education is needed to impart this knowledge.
- Bandwidth: Satellite bandwidth is a scarce resource. Hence, less bandwidth is available for satellite phone users, resulting in a lower achievable data rate.
Cell Phone or Mobile Phone: Based on Cellular Networks
Cellular mobile phones operate on cellular networks consisting of a network of cell towers or base stations on the ground. These cell towers support various radio access technologies (RATs) such as GSM, CDMA/UMTS, 4G LTE, and 5G NR at different frequency bands. These cell towers are installed relatively closer to the cell phone users compared to satellites.
When a user initiates a call, the cell phone sends a signal to the nearest cell tower or base station. This signal is relayed to the mobile switching center (MSC) or base station controller (BSC). The MSC is the central hub of the cellular network, which manages call routing and other network functions. The call is then routed to the recipient’s network, and a two-way voice channel is established when the recipient answers.
Image Alt Text: Cellular Network
Here are some features of cell phones and their corresponding cellular mobile network system:
- Network Usage: Mobile phones use cellular networks such as GSM, CDMA, and LTE to dial or receive calls.
- Typical Use Cases: Mobile phones are mainly used in city areas where there are larger populations.
- Cost: Mobile phones are very cheap, and many options are available to purchase.
- Functionality: Internet services and other advanced features for high data rate applications are already available in cellular networks. They are used for voice, data-based apps, SMS, MMS, VOIP, and more.
- Connectivity: Call drops due to handover are a big concern while traveling and moving from network to network. It often requires a new SIM and even a new mobile phone to be purchased in different countries, depending on the availability of cellular network types such as GSM (i.e., 2G), CDMA (i.e., 3G), LTE (i.e., 4G), or LTE advanced.
- Service Provider Benefits: Cellular networks offer major benefits to telecom service providers due to the high population density as target users of the cellular services.
- Network Installation: Installation of a cellular network is easy and requires fewer resources and less time. A cellular network consists of a mobile phone, a Base station (i.e., BTS), and cellular infrastructure (MSC, PSTN, ISDN, PSDN, Wi-Fi interface, etc.).
- Maintenance: Maintenance of a cellular system is simple and less costly.
- Ease of Use: Mobile phones have already penetrated the market and are used by a huge population across the world. People have become familiar with the use of mobile phones and cellular systems. Moreover, many technicians are available in almost every street of developed and developing countries.
- Bandwidth: Bandwidth in cellular networks is not a concern due to advanced multiple access and modulation techniques such as MIMO, OFDM, and OFDMA. Hence, high bandwidth and consequently high data rates can be achieved easily.
Comparing Satellite Phones vs. Cell Phones
The following table highlights the differences between satellite phones and cell phones with respect to various parameters:
| Parameters | Satellite Phone | Cell Phone |
|---|---|---|
| Network type used | Sat phones use satellites installed in LEO around the Earth for their operation. | Cellular mobile phones use cellular networks (GSM, UMTS, 4G LTE, 5G NR) installed by service providers. |
| Call drop | No such issue | Big concern when traveling from network to network within the same RAT or another RAT |
| Transmit power | Higher (About 2 watts to 5 watts or even higher, varies as per specific model and satellite network) | Lower (0.1 to 2 watts, varies as per frequency band and cellular technology used) |
| Communication transmit and receive frequencies | L band (1616 to 1626.5 MHz for the uplink direction from the phone to the satellite and 1626.5 to 1660.5 MHz for the downlink direction from the satellite to the phone. | Cellular mobile phones communicate using various cellular band frequencies as per their technologies such as GSM, CDMA/UMTS, 4G LTE, 5G NR, 6G, etc., and region-wise allocations in each of these technologies. The 2G GSM phones use 850 MHz, 900 MHz, 1800 MHz, and 1900 MHz frequencies, 4G LTE phones use 700, 800, 850, 900, 1700, 1800, 1900, 2100, and 2600 MHz range frequencies, and 5G phones use sub-6GHz and millimeter wave bands, and so on. |
| Antenna | Sat phones require an extendable or foldable antenna to establish a line of sight (LOS) connection with satellites. | Cell phones require an internal antenna or small external antenna to communicate with cellular tower antennas |
| Battery power consumption | Higher, due to high transmit power, longer distance, longer call setup time, and signal processing requirements. | Lower, due to low transmit power, shorter distance, and faster call setup time |
| Voice call quality | Offers lower quality due to longer signal delay and high atmospheric interference | Offers higher quality due to fast call setup and less interference |
| Data services | Provides basic data services with slow speeds for email and basic internet | Provides fast internet services with 2G, 3G, 4G, and 5G networks |
| Availability and accessibility | May require an unobstructed view of the sky for a satellite connection | Widely available and accessible in urban and suburban areas where cellular infrastructures are available |
| Roaming charges | No such charges | Roaming charges apply outside the home area of subscribers |
| Cost | Generally, satellite phones are expensive | Cellular phones are more affordable |
Conclusion
Both satellite phones and cell phones offer unique benefits in their specific usage applications. The choice between a cell phone and a satellite phone depends on the user’s specific needs and the intended usage scenario. Satellite phones are invaluable for communication in remote or disaster-afflicted areas with no cellular coverage, whereas cell phones excel in areas with an established cellular network.
