What is sXGP
A wireless communication system based on TD-LTE, one of a world standards, using unlicensed band 1.9GHz. While following the concept of PHS, it is a self-employed communication system that extends its functionality based on the 4G (LTE) system currently used in mobile routers and smartphones.
Uses LTE Technology
- High Security
- WLess electromagnetic interference than WiFi
- LTE ecosystem ensures
stable, continuous and low cost of equipment supply
No license required just like PHS
- Free installation without license procedures
- Portability
- Low installation and operation cost
Data communication and voice calls
are available
- High quality voice communication VoLTE
- high-speed data communication
- Collaborate with PBX
The technical specification of sXGP uses TD-LTE system, which is part of the LTE standard for 4G (fourth generation) mobile phones. As it is the "Self-Organizing Network", the owner of buildings, factories can install and operate their own facilities and communicate and make phone calls on site. In addition to being used as an extension phone for businesses operating vast facilities, it is also expected to be used as a wireless communication infrastructure for IoT (Internet of Things), which promotes automation by linking sensor devices and control devices. In addition, sXGP can be used with existing smartphones, not specialized machines. It also can promote and contribute to digitalization and IoT of equipment by utilizing 4G high-speed and stable communication, deploying various sensors in factories and distribution centers and networking with sXGP.
sXGP Standardization Trends
sXGP was institutionalized in Japan in October 2017. Systems uses 5 MHz (1896.6 to 1901.6 MHz) in the 1.9 GHz band
The first edition of ARIB STD-T118 was established on July 26, 2018.
As the public PHS service ended in March 2023, the system was reviewed, and as of March 2024, 4 waves (1888.5 to 1893.5 MHz, 1896.6 to 1901.6 MHz, 1911.6 to 1916.6 MHz) of 5MHz width and 1 wave (1906.6~1916.6MHz) of 10MHz width are available.
sXGP frequency band
Included in Band 39 (international frequency band of LTE defined by 3GPP). Many LTE-enabled devices are supported.
sXGP`s superiority
sXGP is the successor service to self-employed PHS (or Private PHS) and advanced PHS (voice + data communication, high security). The general PHS service ended in January 2021, and the telemetering service also ended in March 2023. sXGP can be implemented not only in voice communication but also in the current mobile data communication environment such as data utilization, video and video conferencing.
In addition to communication terminals, self-employed PHS can use smartphones as terminals in sXGP, which improves convenience and mobility and can be used for various purposes.
| sXGP | Wi-Fi | Local 5G | |
|---|---|---|---|
| Functional Performance | 4G Performance （DL: Up to 40Mbps ） | Limited | 5G （High speed・Low Latency・High Capacity） |
| Frequency | Nearly Dedicated | Shared and unmanageable | Dedicated |
| Security | Firm （SIM authentication） | Vulnerable （PW method） |
Firm （SIM authentification） |
| Cover Area | Wide （Radius:several hundred meters） | narrow （Radius:1 hundred meter） |
Wide （Radius:tens to hundreds of meters） |
| Cost | Relatively Inexpensive （LTE technology promoted） | Low Price （well-spread） | Considerably Expensive （Not yet widespread） |
| Installation & Operation Degrees of Freedom | Free （No license, AP is movable） |
Free （No license, AP is movable） | Difficult （License required、AP is unmovable） |
sXGP`s superiority①Handover
Since sXGP is an LTE system, the switching time for handover between access points is very short. Therefore, it is suitable for use in IoT communications.
With general Wi-Fi, handover switching takes a long time, and data communication is interrupted during that time.
sXGP`s superiority②Cover Area
sXGP uses 1.9GHz, so it can provide a relatively wide coverage area.
sXGP`s superiority③VoLTE【In progress】
VoLTE (Voice over LTE)
VoLTE is a dedicated technology for transmitting voice over LTE networks. It uses the AMR-WB (Adaptive Multi-Rate Wideband) codec, enabling natural reproduction of voice from low to high frequencies. Although voice data is transmitted as IP packets, a mechanism called QoS (Quality of Service) assigns the highest priority to voice communication. This ensures voice quality remains stable and less affected by other data transmissions. VoLTE provides optimized bandwidth and processing specifically for voice calls.
● High Audio Quality:By using wideband codecs such as HD Voice (AMR-WB), it delivers clearer and more natural-sounding voice.
● Low Latency:Since voice calls are given high priority, delays are minimized, allowing smooth conversations.
● Stability:With dedicated quality control mechanisms, voice quality is maintained even during network congestion.
● Merit:Users can use LTE's high-speed data communication simultaneously while on a call.
VoIP, often compared with VoLTE, offers advantages in terms of lower costs, multifunctionality, and flexibility with devices and networks. However, VoLTE is more highly regarded when it comes to communication quality.
Comparison of Communication Quality: VoLTE vs. VoIP
| VoLTE | VoIP | |
| Priority | Highest priority with QCI = 1 | Best-effort (no priority) |
| Latency | Guaranteed to be under 150 ms | Increases during network congestion |
| Packet Loss Handling | Uses dedicated bandwidth to minimize loss | Mitigated by jitter buffers |
VoLTE vs. VoIP:
Voice Communication Quality Comparison Test（Data provided by Baicells Japan Co., Ltd.）
● VoLTE maintains high voice quality even when the network is congested due to an increase in users or data traffic, thanks to the QoS (Quality of Service) mechanism.
● VoIP can offer high voice quality when the network is not busy, but as network congestion increases, the voice quality degrades.
Test Results: Changes in MOS Value and R Value
- VoLTE Maintains Quality Even as Simultaneous Call Count Increases.
- Even under heavy network traffic, such as during simultaneous voice and data transmission, VoLTE maintains stable and reliable call quality.
【Test Conditions】
- A simulator capable of emulating 128 users was connected to a full set of sXGP C-RAN radio equipment, and voice call tests were conducted using both VoIP and VoLTE methods.
- For the VoIP call test, the G.711u codec was used and gor the VoLTE test, the AMR-WB codec was used.
sXGP Use Cases
Warehouse Factory
sXGP is effective in solving problems such as the difficulty of receiving general mobile phone signals in large warehouses and factories, and the high costs involved in setting up Wi-Fi.
Large-scale plants
sXGP is an effective and unique means of communication that can cover vast territory.
Commercial Facilities
Commercial facilities may have many tenants living in the same building, and by building and providing sXGP as a unique communication system for facility management, we can meet a variety of needs. sXGP is also effective as a BCP measure in the event that the public communication network goes down due to a disaster, etc.
Hospitals and Nursing Homes
Of the approximately 8,600 hospitals in Japan, approximately 80% use internal PHS, and data shows that approximately 80% of these hospitals would like to continue using PHS. Using the same frequency, sXGP, which has the same low output as PHS, can solve the problems faced by many hospitals.