Return on Investment (roi) for Multi-Technology son juan Ramiro, Mark Austin and Khalid Hamied

7.3.4.2. Combining Voice and Data Traffic

Since live operational networks have a combination of voice and data traffic, the combination of both needs to be addressed in order to compute aggregated, normalized traffic metrics in the radio interface and in E1 links. When assessing the need for capacity expansions, it can be considered that the maximum amount of normalized traffic per sector that can be served through a single carrier is 100 ‘normalized carrier traffic units’ (200 for two carriers, 300 for three carriers, etc.), although more conservative exercises can be done, for example assuming that the maximum traffic per carrier (from a radio perspective) is 80 or 90 ‘normalized carrier traffic units’. Similarly, the maximum amount of normalized traffic that can be served through a single E1 link is 100 ‘normalized E1 traffic units’ (200 for two E1 links, 300 for three E1 links, etc.) and conservative (lower) thresholds can also be applied. A straightforward and simplistic way to combine and normalize voice and data traffic is described in the following equations.
⎛ TVoicePerSector + TDataPerSector ⎞⎟⎠ (7.5) Tsector = 100⋅⎜⎝TMaxVoicePerCarrier TMaxDataPerCarrier
⎛ TVoicePerSite + TDataPerSite ⎞⎟⎠ (7.6)
TIub = 100⋅⎜⎝TMaxVoicePerE1 TMaxDataPerE1
where T_sector is the normalized radio traffic per sector, T_{VoicePerSector} is the voice traffic per sector (in Erlangs), T_{MaxVoicePerCarrier} is the maximum voice traffic per sector and carrier (in Erlangs) when there is no data traffic, T_{DataPerSector} is the data traffic per sector (in kbps) and T_{MaxDataPerCarrier} is the maximum data traffic per sector and carrier (in kbps) when there is no voice traffic. Similarly, T_Iub is the normalized Iub traffic per site, T_VoicePerSite is the voice traffic per site (in Erlangs), T_{MaxVoicePerE1} is the maximum voice-only traffic per E1 link (in Erlangs), T_DataPerSite is the data traffic per site (in kbps) and T_MaxDataPerE1 is the maximum data-only traffic per E1 link (in kbps).