peater. Either way, line-of-sight point-to-point engineers argue that narrow beam width dish anten- nas are the most effective way to achieve link budget gain (and by implication, throughput) with the wide choice of available frequency bands, meaning that an optimum choice of system can usually be made. 13.2.1 Point-to-Multipoint Another alternative option is point-to-multipoint microwave. In point-to-multipoint a sectored antenna with for example a 90-degree beam width will service multiple sites, typically of the order of nine or SO. The band options are ETSI standard 10.5 GHz, 26 GHz and 28 GHz. Bandwidths are presently 7, 14 and 28 MHz and throughput scales to 150 Mbps per sector with modulation options ranging from QPSK to 256 QAM. The systems are normally duplex with a duplex spacing of the order of 350 MHz at 10.5 GHz or 1008 MHz at 26 and 28 GHz. Output power is +20 dBm at 10.5 GHz and +18 dBm at 26 or 28 GHz. A 90-degree sectored antenna at the base station at 10.5 GHz provides 15 dBi of gain at 10.5 GHz and 17 dBi of gain at 26 or 28 GHz. A 0.3-m dish at the other end gives 28 dBi of gain at 10.5 GHz, 36 dBi at 26 GHz and 37 dBi at 28 GHz. Increasing the dish size to 0.6 m increases the gain to 33 dBi at 10.5 GHz, 40.5 dBi at 26 GHz and 42 dBi at 28 GHz. 2 The spectral efficiency argument is based on the multiplexing and scheduling gain achievable from point-to-multipoint and its impact on backhaul efficiency and throughput. A microwave point-to-point connection achieves a similar scheduler gain to the one-to-one gain achieved in the RAN. A microwave point-to-multipoint connection achieves the same one-to-one scheduler gain but has additional gain from multiuser diversity. Point-to-multipoint backhaul is therefore conceptually similar to a sectored node or e node B. Throughput in terms of joules per bit may also be lower, offering operational cost benefits, for example in solar-powered or diesel- powered applications. Point-to-multipoint could potentially be more broadly deployed but limited vendor supp