Software platforms of 5G



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SOFTWARE PLATFORMS OF 5G


The Open-Air Interface(OAI) platform includes a full software implementation of fourth generation mobile cellular systems which complies with 3GPP LTE standards which is coded in C language under real-time Linux which dedicated for x86. At the physical layer, it provides the following features:

  • LTE release 8.6, with a subset of Release 10;

  • FDD and TDD configurations in 5, 10 and 20 MHz bandwidth;

  • Transmission mode: 1 (SISO), and 2, 4, 5, and 6 (MIMO 2x2);

  • CQI/PMI reporting;

  • HARQ support (UL and DL);

  • Highly optimized baseband processing (including turbo decoder).

This are the operations made and practically defined when the LTE was new. Currently, MATLAB has performed some operations to generate the type of signals which would be expected during 5G. We have picked MATLAB simulations to define the different results being obtained between WLAN (Wireless Local Area Network), LTE (Long Term Evolution) and LTE A (LTE Advanced) and 5G.

3.1 Wireless Local Area Network(WLAN):

As a necessity, wireless connectivity for computers has been well established and basically all new laptops have a Wi-Fi capability. The WLAN solutions that are available the IEEE 802.11 standard, often termed as Wi-Fi has become the de-facto standard. With operating speeds of systems using the IEEE 802.11 standards of around 54 Mbps being commonplace, Wi-Fi can compete well with wired systems.

To increase the flexibility and performance of the system, Wi-Fi “hotspots” are widespread and in common use. These enable people to use their laptop computers as they wait in hotels, airport lounges, cafes and many other places using a wire-less link rather than needing to use a cable.

In addition to the 802.11 standards being used for temporary connections, and for temporary Wireless Local Area Network, WLAN applications, they may also be used for more permanent installations. In offices WLAN equipment may be used to provide semi-permanent WLAN solutions. Here the use of WLAN equipment enables offices to be set up without the need for permanent wiring, and this can provide a considerable cost saving. The use of WLAN equipment allows changes to be made around the office without the need to re-wiring.

As a result, the Wi-Fi, IEEE 802.11 standard is widely used to provide WLAN solutions both for temporary connections in hotspots in cafes, airports, hotels and similar places as well as within office scenarios.

IEEE 802.11 standards: There is a plethora of standards under the IEEE 802 LMSC (LAN/MAN Standards Committee). Of these even 802.11 has a variety of standards, each with letter suffix. These covers everything from the wireless standard themselves, so standards for security aspects, quality of service and the like:



  • 802.11a - Wireless network bearer operating in the 5 GHz ISM band with data rate up to 54 Mbps.

  • 802.11b - Wireless network bearer operating in the 2.4 GHz ISM band with data rates up to 11 Mbps.

  • 802.11e – Quality of service and prioritization.

  • 802.11f – Handover.

  • 802.11g – Wireless network bearer operating in 2.4 GHz ISM with data rates up to 54 Mbps.

  • 802.11h – Power control.

  • 802.11i – Authentication and encryption.

  • 802.11j – Interworking.

  • 802.11k – Measurement reporting.

  • 802.11n – Wireless network bearer operating in the 2.4 and 5 GHz ISM bands with data rates up to 600 Mbps.

  • 802.11s – Mesh networking.

  • 802.11ac – Wireless network bearer operating below 6GHz to provide data rates of at least 1Gbps per second for multistation operation and 500 Mbps on a single link.

  • 802.11ad – Wireless network bearer providing very high throughput at frequencies up to 60GHz.

  • 802.11af – Wi-Fi in TV spectrum white spaces (often called White-Fi).

  • 802.11ah – Wi-Fi using unlicensed spectrum below 1 GHz to provide long range communications and support for the Internet of Everything.

The most widely used standards known are the network bearer standards, 802.11a, 802.11b, 802.11g and the latest well known is 802.11n.

Network bearer standards 802.11: All the types of 802.11 bearer Wi-Fi standards operates within the ISM (Industrial, Scientific and Medical) frequency bands. These standards are shared by a variety of other users, but no license is required for the operation within these frequencies. This provides access to the general systems for the widespread use.

There are several bearer standards which are commonly used. These are the 802.11a, 802.11b, and 802.11g standards. The latest WLAN standard used is 802.11n which provides raw data rates of up to 600 Mbps.

All types of bearer standards are different and with respect to they have different specifications, features and were launched at different times. The first accepted WLAN standard was 802.11b. This standard used the frequencies in the 2.4 GHz Industrial Scientific and Medical (ISM) frequency band, which offered raw and over the air data rates of 11 Mbps using a modulation scheme known as Complementary Code Keying (CCK) as well as supporting Direct-Sequence Spread Spectrum (DSSS) which comes from the first introduced 802.11 specification. Similarly, the second standard 802.11a was defined which can use a different modulation technique, Orthogonal Frequency Division Multiplexing (OFDM) used the 5GHz ISM band. Of these two standards, it was the 802.11b which became popular because the chips for the lower 2.4 GHz band were easier and cheaper to manufacture. Hence this popular 802.11b standard became the main Wi-Fi standard. Hence to obtain higher speeds, the new version was introduced which was 802.11g and was launched in June 2003. It used the same 2.4 GHz band with OFDM and offered data rates of up to 54 Mbps, same as 802.11b. It offered the backward compatibility to the 802.11b. So, in the latest the WLAN bearer standard 802.11g were used.

Moving forward, In January 2004, the IEEE announced that it had a new team which is developing an even higher speed standard. 802.11n was being established at that time similarly to the 802.11g. It was getting accepted by the industry in early 2006. Hence with the complete understanding for the hardware requirements it was introduced in 2007.

802.11 Networks: There are two types of networks they are Infrastructure networks and Ad-hoc networks. The infrastructure networks are aimed at the office areas or to provide ‘hotspot’. The WLAN equipment is flexible and can be installed where intended instead of a wired system providing restrictions and can provide considerable cost savings. The wired network would be required to get connected to the server. The wireless network is then split up into several cells each serviced by a base station or Access point (AP) which would act as a controller for the cell. Each Access point may have a range of between 30 and 300 meters depending on the environment and the location of Access point.

The other type of networks are Ad-hoc networks. These networks come in to existence when computer and peripherals are brought together. They may be needed when several people come together and would require sharing the data or if they need to access the printer without the need of using the wire connections. With such circumstance the user can only communicate with each other but not with the larger wired network. As a result, there is no Access point and special algorithms within the protocols are used to enable one of the peripherals to take over the role to control.





802.11A

802.11B

802.11G

802.11N

Date of standard approval

July 1999

July 1999

June 2003

Oct. 2009

Maximum data

rate (Mbps)

54

11

54

~600

Modulation

OFDM

CCK or DSSS

CCK, DSSS, or OFDM

CCK, DSSS, or OFDM

RF Band(GHz)

5

2.4

2.4

2.4 or 5

Number of

spatial streams

1

1

1

1,2,3, or 4

Channel width (Mhz) nominal

20

20

20

20 or 40


Figure 8: Summary of major 802.11 Wi-Fi Standards




WLAN SIMULATIONS RESULTS FROM MATLAB:

WLAN transceiver:





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