Carsten, around the edges of the patch are all fringing fields, so the
required coupling to the plane may be quite low, depending on the design.
The compromised ground plane may also be permitting some rear size
pickup - multipath !
I'll do some EM modelling later to try and put some numbers
On 5/31/22 3:23 AM, Carsten Andrich via time-nuts wrote:
On 31.05.22 01:10, glen english LIST via time-nuts wrote:
Be aware not to confuse the antenna ground plane (the patch will
always have its own plane because the top metalization must be fed
against a plane or counterpoise - and a
On 31.05.22 01:10, glen english LIST via time-nuts wrote:
Be aware not to confuse the antenna ground plane (the patch will
always have its own plane because the top metalization must be fed
against a plane or counterpoise - and a ground plane behind the antenna.
I can see the usefulness of
Be aware not to confuse the antenna ground plane (the patch will always
have its own plane because the top metalization must be fed against a
plane or counterpoise - and a ground plane behind the antenna.
I can see the usefulness of the larger ground plane for any purchased
patch antenna to
Erik,
The NEO-7M may have sawtooth correction output, have you checked that
and made compensations?
Since the oscillator is not steered and free-floating, the
cycle-assignment of the PPS may be less than optimal so just measuring
that without the compensation can cause a wider range of PPS
Hi
The variation you see is dependent on a number of things. One of them is space
weather. If you do your run during a very active period ( typically peak sun
spots)
you may see some very dramatic swings on a single band device.
Bob
> On May 30, 2022, at 3:00 AM, Erik Kaashoek via time-nuts
Hi Erik,
have you tried running all receivers off the same antenna via a power
splitter (make sure to dc block all but one receiver)? That should
remove the uncertainty due to antenna differences (location, RF
characteristics, etc.).
Also, are you using ground planes for your puck antennas?
Further evaluation did shown the time differences between the 3 GPS
modules was due to difference in the trigger level setting of the
timer/counter and difference in length of GPS antenna cables.
After removal of the phase drift due to Rb frequency offset the attached
image shows the phase
