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...rmation about the time resource allocation in the primary system. Moreover, it does not have knowledge about the primary transmit input symbol vector, thus techniques such as dirty paper coding (DPC) =-=[10]-=- can not be implemented. Let us consider the classic OFDM receiver chain, where the following baseband preprocessing is performed ỹp = FByp = H̃ppAF −1sp + H̃spxs + ñp (4) ỹs = FBys = H̃psAF −1sp +...

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...on (CSI) to allow the coexistence of macro- and small-cells. This is done through the use of a null-space precoder that protects the macro- from small-cells transmissions. Interference alignment (IA) =-=[5]-=- can also be used if CSI is globally available in the network. In particular, if multiple spatial dimensions are available at one of the tiers, i.e. for multiple input multiple output (MIMO) systems, ...

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...nted to deal with both cross- and cotier interference if the two tiers cooperate. When no cooperation is possible (or desirable), techniques based on dynamic spectrum access (DSA) and cognitive radio =-=[3]-=- are a solution, due to their capability to adapt intelligently to the environment. One DSA technique, called Vandermonde-subspace frequency division multiplexing (VFDM) [4], uses the frequency dimens...

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... On the one hand, if the two tiers communicate over the same bandwidth the overall spectral efficiency increases, while on the other hand, high levels of interference are generated. Joint beamforming =-=[1]-=- or cooperative frequency reuse [2] strategies can be implemented to deal with both cross- and cotier interference if the two tiers cooperate. When no cooperation is possible (or desirable), technique...

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...de an effective crosstier interference management [6]. Additionally, if the cognitive tier is aware of the power allocation in the primary tier, solutions such as opportunistic interference alignment =-=[7, 8]-=- can be adopted to for the coexistence. In this contribution, we focus on a two-tiered network, whose licensee macro-cell base station (MBS) is OFDM based and oblivious of a cognitive secondary base s...

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... (DSA) and cognitive radio [3] are a solution, due to their capability to adapt intelligently to the environment. One DSA technique, called Vandermonde-subspace frequency division multiplexing (VFDM) =-=[4]-=-, uses the frequency dimension and perfect channel state information (CSI) to allow the coexistence of macro- and small-cells. This is done through the use of a null-space precoder that protects the m...

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...communicate over the same bandwidth the overall spectral efficiency increases, while on the other hand, high levels of interference are generated. Joint beamforming [1] or cooperative frequency reuse =-=[2]-=- strategies can be implemented to deal with both cross- and cotier interference if the two tiers cooperate. When no cooperation is possible (or desirable), techniques based on dynamic spectrum access ...

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... In particular, if multiple spatial dimensions are available at one of the tiers, i.e. for multiple input multiple output (MIMO) systems, IA can provide an effective crosstier interference management =-=[6]-=-. Additionally, if the cognitive tier is aware of the power allocation in the primary tier, solutions such as opportunistic interference alignment [7, 8] can be adopted to for the coexistence. In this...

Citation Context

...de an effective crosstier interference management [6]. Additionally, if the cognitive tier is aware of the power allocation in the primary tier, solutions such as opportunistic interference alignment =-=[7, 8]-=- can be adopted to for the coexistence. In this contribution, we focus on a two-tiered network, whose licensee macro-cell base station (MBS) is OFDM based and oblivious of a cognitive secondary base s...