上浒充通大学 Network Architecture SHANGHAI JIAO TONG UNIVERSITY ▣Two-Tier Network Primary Network C licensed channels(orthogonal) A.=1 Secondary Network If channel jwas assigned to link e Represented by graph G=(V,E) Channel assignment history(matrix A) Currently unavailable channels:set I -Data Flow PU Base Station Data Link SU Router Flow Initiator 11
11 Network Architecture ❑ Two-Tier Network ➢ Primary Network ⚫ C licensed channels (orthogonal) ➢ Secondary Network ⚫ Represented by graph G=(V,E) ⚫ Channel assignment history (matrix A) ⚫ Currently unavailable channels: set , 1 Ae j = If channel j was assigned to link e
Flow Interference Model 上游充通大学 SHANGHAI JIAO TONG UNIVERSITY ▣Flow Model >M concurrent and constant data flows >Routing Source and Destination:(S D) Flow parameters:rate r and packet size ▣Interference Model Transmission succeeds if the interference neighborhood is silent. Resemble CSMA/CAin IEEE 802.11 -Interference link The interference neighborhood of link e:I(e) linke Interference Contention for transmission opportunities! neighborhood Ife)
12 Flow & Interference Model ❑ Flow Model ➢ M concurrent and constant data flows ➢ Routing Source and Destination: ➢ Flow parameters: rate and packet size ❑ Interference Model ➢ Transmission succeeds if the interference neighborhood is silent. ➢ Resemble CSMA/CA in IEEE 802.11 k r ( , ) k k S D k The interference neighborhood of link e: I e( ) link e Interference neighborhood I(e) Interference link Contention for transmission opportunities!