The approach adopted by TRAI is first to examine the technical aspects of 

Spectrum Efficiency and then build in the economic aspects to provide a 

comprehensive view to the stakeholders for discussion. 

3.1.2  Other measures of Spectral Efficiency  

As explained in the previous section, Erlang / MHz / Sq. Kms indicates the 

Erlang density supported per unit of spectrum and thus gives the geographic 

intensity with which the network deploys the spectrum and is the measure for 

the assessment of spectrum utilisation in this exercise. 

Other ways of expressing spectral efficiency: 

- 

Effective Reuse   describes how often the same frequency is re used in 

the network.  Effective re use is equal to the total number of frequencies 

used divided by the average number of TRx per sector.  This measure 

does not indicate if the radio resource is fully loaded. 

- 

Fractional Load    measures the efficiency of frequency hopping networks 

in relation to effective frequency re use. 

- 

Frequency Allocation Re use(FAR)  indicates how closely the frequencies 

are actually re used in a network.  FAR equals the total number of 

frequencies used divided by the average number of frequencies in the 

Mobile Allocation lists

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 (MA lists).  This measures the ability of hopping 

networks to implement tight re use.  If fractional loading is not used then 

frequency allocation re use is the same as effective re use. 

- 

Frequency Load   indicates how much traffic is carried by the available 

spectrum.  Frequency Load is equal to the busy hour timeslot occupation 

multiplied by the Fractional Load. 

- 

Effective Frequency Load   quantifies the loading of each frequency in the 

system. 

3.2 

Methodology for evaluating the technical spectrum efficiency of 

Service Providers 

3.2.1  Spectral efficiency concept 

The performance of a network in terms of load and quality is shown in Fig 3.1. 

Network 1 and Network 2 can be different networks or the same network with 

added functionality.  Network 2 is more spectrally efficient than Network 1 

because, for the same quality level it can carry more traffic for a given amount 

of spectrum.  The relative value of this additional traffic load is the capacity 

provided by the added functionality. 

5

 The frequency hopping list is given by the Mobile Allocation list. 

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