Slow-fast programming of distributed base stations in a wireless network
View Patent ↗A slow fast programming method for efficient remote field update in distributed base stations overcomes significant fiber propagation delay associated with a remote unit by applying programming data at two clock frequencies. A fast clock frequency is used for programming data phases that do not require a response from the remote unit, and a slow clock frequency is used for programming data phases that require a response from the remote unit. Testing a base unit and a remote unit is also accomplished with more than one clock based on the test dependence on a remote response.
1. In a system with a base unit operably connected to a remote unit by a link and wherein there is a propagation delay associated with the length of the link, a method for providing efficient programming of the remote unit, wherein a first phase of programming data requires a response from the remote unit and second phase of programming data does not require a response from the remote unit, comprising:
selecting a fast clock frequency;
determining a slow clock frequency based upon the round trip propagation delay associated with the link between the base unit and the remote unit; and
transmitting the phases of programming data at the fast clock frequency or the slow clock frequency based on the whether the programming data is from the second phase or first phase of programming data respectively;
wherein the first phase of programming data comprises programming data associated with Boundary Scan (BS) testing.
2. The method according to claim 1 , wherein the round trip propagation delay is greater than the fast clock period.
3. The method according to claim 1 , wherein the length of the link is greater than 1 km.
4. The method according to claim 1 , wherein the length is equal to or less than 12 km.
5. The method according to claim 1 , wherein the step of determining the slow clock frequency comprises a ping test.
6. The method according to claim 5 , wherein the base unit sends a signal at a clock frequency to the remote unit and monitors for a proper response.
7. The method according to claim 6 , wherein if the base unit does not receive a proper response, the clock frequency is reduced until the base unit receives a proper response.
8. The method according to claim 1 , wherein the first phase of programming data is selected from the group comprising Boundary Scan (BS) chain integrity check and readback verification.
9. The method according to claim 1 , wherein the second phase of programming data is selected from the group comprising erase and memory programming.
10. In a system with a base unit operably connected to a remote unit by a link and wherein there is a propagation delay associated with the length of the link, a method for performing boundary scan testing of the base unit and the remote unit, the method comprising:
performing a first testing phase using a clock frequency having a period greater than the round trip propagation delay associated with the link, wherein the first testing phase requires a response from the remote unit, wherein the first testing phase includes Boundary Scan (BS) testing; and
performing a second testing phase using a clock frequency having a period less than the round trip propagation delay associated with the link, wherein the second testing phase does not require a response from the remote unit.
11. The method according to claim 10 , wherein the base unit is a base band unit and the remote unit is radio frequency unit.
12. The method according to claim 10 , wherein the link is a serial single bit fiber.
13. The method according to claim 10 , wherein the system is distributed base station.
14. In a system having a base unit operably connected to a remote unit and wherein there is a round trip propagation delay between the base unit and the remote unit, a method for serially transmitting update data to the remote unit, the method comprising:
transmitting a first portion of the update data at a first test clock frequency, wherein the first portion of the update data is update data requiring a response from the remote unit, wherein the first portion of the update data comprises update data associated with Boundary Scan (BS) testing, wherein the first test clock frequency is selected such that the period of the first test clock frequency is greater than the round trip propagation delay; and
transmitting a second portion of the update data at a second test clock frequency, wherein the second portion of the update data is update data not requiring a response from the remote unit, wherein the second test clock frequency is selected such that the period of the second test clock frequency is less than the round trip propagation delay.
15. The method of claim 14 , wherein the remote unit comprises a programmable ROM.
16. The method of claim 14 , wherein the system is a distributed base station.
17. The method of claim 14 , wherein the round trip propagation delay is a function of the distance between the base unit and the remote unit.
18. The method of claim 14 , wherein the second test clock frequency is more than 10 times greater than the test clock frequency.
19. The method of claim 18 , wherein the second test clock frequency is greater than 100 times the test clock frequency.
20. The method of claim 17 , wherein the base unit and remote unit are operably connected by a serial fiber cable.