What is GSM time slot?

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Introduction. The GSM standard [1] specifies a TDMA frame as a combination of 8 time slots. Each time slot has a duration of 3/5200 seconds (about 0.577 ms) and a time slot number (TN) from 0 to 7. GSM frames use GMSK modulation, where one symbol is equivalent to one bit. Each time slot is 156.25 bits long.

What is the duration of GSM Sacch multiframe?

This lasts for approximately 4.615 ms (i.e.120/26 ms) and it forms the basic unit for the definition of logical channels. One physical channel is one burst period allocated in each TDMA frame.

What is multiframe in GSM?

A GSM Multiframe is the basic unit, and is 120 ms long. There are 26 Frames in each Multiframe, with each Frame being 4.61538 ms long (120 ms/26). Within each Frame are 8 Timeslots at 576.92 μs per Timeslot (577 μs in round numbers). Finally, there are 156.25 Bits per Timeslot, each Bit being 3.69231 μs long.

How many frames are possible in GSM?

The GSM frame structure is designated as hyperframe, superframe, multiframe and frame. The minimum unit being frame (or TDMA frame) is made of 8 time slots. One GSM hyperframe composed of 2048 superframes.

What is GSM timing advance?

In the GSM cellular mobile phone standard, timing advance (TA) value corresponds to the length of time a signal takes to reach the base station from a mobile phone.

What is time slot in mobile communication?

Time slots are the smallest division of a communication channel that is assigned to particular users in a communication system. Time slots can be combined for a single user to increase the total data transfer rate available to that user. In some systems, time slots are assigned dynamically on an asneeded basis.

What is the duration of a super frame?

The active period of the superframes is called as superframe duration (SD). Every SD is composed of 16 time periods with equal lengths.

Why 26 training bits are required in all the normal GSM time slots?

There is a total of eight different bit sequences that may be used, each 26 bits long. The same sequence is used in each GSM slot, but nearby base stations using the same radio frequency channels will use different ones, and this enables the mobile to differentiate between the various cells using the same frequency.

What is GSM burst?

This GSM burst structure is used to ensure that it fits in the time slot regardless of any severe timing problems that may exist. Once the mobile has accessed the network and timing has been aligned, then there is no requirement for the long guard period.

What is a Hyperframe?

Hyperframe A Hyperframe is a hierarchical frame structure. In GSM the Hyperframe is either 2048 (normal) or 1024 (classic) Superframes , this depends on the configuration.

What is the raw data rate of GSM?

Data at 9.6 kbit/s For reliable communication at a user bit rate of 9.6 kbit/s, the data terminal initially encodes the raw data, giving a bit rate of 12 kbit/s. That is, 12 kbit/s is the bit rate over the interface between the GSM handset and the data source (PC, fax or whatever).

How can calculate advance time in GSM?

1/2*3.7 μs /bit*63bit*c=35km {In the formula, 3.7μs /bit is the duration per bit (156/577); 63bit is the maximum bit number of the time adjustment; c is the light speed (transmission speed of the signal); and ½ indicates that the go and return trip of the signal.}

What is the distance of GSM module?

GSM module located by Timing advance and GSM sector antenna With radio waves travelling at about 300 meters per microsecond, one TA step then represents a change in round-trip distance (twice the propagation range) of about 1100 meters.

What is network time slot?

Slot time is a concept in computer networking. It is at least twice the time it takes for an electronic pulse (OSI Layer 1 – Physical) to travel the length of the maximum theoretical distance between two nodes.

Why is superframe used?

Superframe is sometimes called D4 Framing to avoid confusion with single-frequency signaling. It was first supported by the D2 channel bank, but it was first widely deployed with the D4 channel bank.

What is GSM used to measure?

Paper is measured in grams per square metre (GSM). The higher the GSM, the heavier and thicker the paper. There are varying weights of GSM paper, meaning you can find the right one for a number of different applications.

What is training sequence in GSM?

The training sequence known as reference signal is used for the channel equalization in time domain when receiving signals for each cell, so that it can improve the anti-interference ability of GSM mobile communication system.

What is GSM protocol?

The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile devices such as mobile phones and tablets.

What is SFN in NR?

In LTE, the arm ticking in 10 ms interval has numbers between 0 and 1023 and these numbers are called SFN (System Frame Number) and the other arm ticking in 1 ms interval has numbers between 0 and 9, and this number is called subframe number.

What is the use of 3 slot time period in GSM?

The 3 slot time period is used by the Mobile subscriber to perform various functions e.g. processing data, measuring signal quality of neighbour cells etc. Engineers working in GSM should know gsm frame structure for both the downlink as well as uplink.

What is the speed of a GSM multiframe?

What are the features of GSM?

GSM – Specification 1 Modulation. Modulation is the process of transforming the input data into a suitable format for the transmission medium. 2 Access Methods. 3 Transmission Rate. 4 Frequency Band. 5 Channel Spacing. 6 Speech Coding. 7 Duplex Distance.

How is data transmitted and received in GSM?

The transmitted data is demodulated back to its original form at the receiving end. The GSM uses Gaussian Minimum Shift Keying (GMSK) modulation method. Radio spectrum being a limited resource that is consumed and divided among all the users, GSM devised a combination of TDMA/FDMA as the method to divide the bandwidth among the users.