Bernard - Appreciate the post.
I'll try to summarize the arguments I'm getting:
1 - Agreed that VOFDM can overcome line-of-sight (LOS) limitations in a best-case scenario.
2 - It is believed by some that despite that fact, the LOS limitations can only be effectively overcome, in less than ideal situations, by the use of repeater stations, as in a cell network. Furthermore, it was felt things would get worse when we go to Hyperlan (5 GHz).
3 - Conceding the point on VOFDM and rain, it was uniformly expressed that snow, sleet, and sub-zero temperatures were bound to degrade signal quality, and therefore, error-free throughput, in VOFDM.
4 - One indicated that this area was hardly within Cisco's demonstrated area of expertise, and felt that they had bought something that cannot be implemented successfully.(Comment: It was certainly within Clarity's area of expertise).
5 - How many overlapping cells (repeaters) need to be installed to overcome LOS limitations (in the worst case, which establishes a practical minimum)? It is suggested by some that to achieve successful throughput, the VOFDM infrastructure cost may, in fact, exceed the WOFDM cost. The argument here is about cost of implementation to achieve a certain quality of throughput. This will require more research; I mention it since it comes as an early response from others who work in this field, some of whom (apparently) have no stake in Wi-LAN.
Back to the research...
Best regards, Jim Kayne |
