Capacity Definition in LTE as Operator level A commonly accepted definition of capacity is the one provided by Shannon which states that capacity is the maximum achievable set of rates in multiple access channels with an arbitrarily small probability of error. As this metric represents a bound in performance, in practice, the sum of the … Read more
Why Operators require Spectrum Reframing in LTE Here I write down one basic idea of Spectrum reframing in LTE and why operators require spectrum reframing for LTE. Operators worldwide are looking forward to new LTE technologies deployment but not every one of them possess brand new spectrum required for LTE deployment. As a result, many … Read more
Analysis of Background Noise in LTE RF Assume that the eNodeB receiver’s IF bandwidth is Bw (unit: MHz), and the eNodeB receive noise figure is Nf (unit: dB), The equivalent noise level of the eNodeB receiver is as follows: No = –174 + 10 log (Bw) + Nf (Unit: dBm) If the demodulation carrier-to-interference ratio … Read more
Theoretical Analysis of Interference by Non Colocated eNodeB Here I write about a simulation analysis of the system performance deterioration caused by the following four types of interference: eNodeB->UE, UE->eNodeB, eNodeB->eNodeB, and UE->UE when two systems are not co-located. From simulation result with no filtering, when the eNodeBs are not co-located, the most serious interference … Read more
Theoretical Analysis of Interference under Site Sharing Here I write about a simulation analysis of the system performance deterioration caused by the following four types of interference: eNodeB->UE, UE->eNodeB, eNodeB->eNodeB, and UE->UE when two systems share the eNodeBs. During simulation, it is assumed that the time percentage of the interference occurrence is 100%, that is, … Read more
Interference between Different Carriers and within same carrier in LTE Absence of synchronization is one of the main sources of interference between TDD based systems belonging to different carriers. The figure below provides a quick view of what will happen if there is asynchronous situation between different networks. Scenarios (a) and (c) described below clearly … Read more
Guard Band Requirement in LTE Here I write on simple how guard band requirement for LTE for 2 option. Guard band requirement LTE verses GSM and guard band requirement LTE FDD verse LTE TDD Guard Band Requirement: LTE-FDD vs GSM/UMTS Configuration is simpler for FDD based systems because both LTE FDD and its neighboring technologies … Read more
Adjacent Channel Interference Ratio for LTE It is difficult to separate Adjacent Channel Leakage power Ratio and Adjacent channel selectivity because they coexist. therefore, Adjacent Channel Leakage power Ratio and Adjacent channel selectivity are usually considered together. The result of the consideration is Adjacent Channel Interference Ratio (ACIR) and Adjacent Channel Interference Ratio is the … Read more
Adjacent channel selectivity and Adjacent Channel Leakage power Ratio for LTE Adjacent channel selectivity (ACS) is a protection index to determine the capability of a receive filter. Adjacent channel selectivity refers to the capability to receive the power of the local in band channel when the interference signal from the adjacent frequency exists. Adjacent channel … Read more
Inter Modulation Interference for LTE When multiple strong signals with different frequencies enter a receiver at the same time, the inter modulation product at the receiver is generated by the signals by the front end due to the non-linear circuit of the receiver. Unfortunately, the frequency of the inter modulation product drops into the useful … Read more