PMP450x Release 24.0 is now available

PMP450x System Release 24.0 is now available at and it is available on cnMaestro.

Release 24.0 introduces the new PMP 450b6 hardware, designed to support the 6 GHz band. This release supports the following new features and enhancements to the 450v platform.

  • Carrier Aggregation
  • AFC Support for Canada Region
  • Support for 30 and 15 MHz channel bandwidths
  • Backward compatibility with legacy PMP 450x SMs

PMP 450b6

The PMP 450b6 expands the high-performance capabilities of the PMP/PTP 450b Series. It excels in various propagation conditions including LOS, near-LOS, and non-LOS scenarios, providing adaptability for diverse deployment environments.

The PMP 450b6 supports a 5.8 GHz band and a 6 GHz frequency band from 5.925 to 6.3 GHz. Using the 6 GHz band requires authorization from the Automatic Frequency Controller (AFC) in the US and Canada. Currently, the PMP 450b6 is not certified to use the 6 GHz band, and Release 24.0 does not support the 6 GHz band on the PMP 450b6. Support for the 6 GHz band will become available in a future release, once the PMP 450b6 is certified.

The PMP 450b6 extends the series’ versatility, leveraging additional spectrum resources to deliver increased capacity, reduced interference, and improved overall performance in wireless communication deployments.


  • Increased capacity
  • Reduced interference
  • Enhanced overall performance

New features

Carrier Aggregation

Release 24.0 introduces support for carrier aggregation in the PMP 450v AP and SM. This release supports up to two carriers, each with a bandwidth of up to 40 MHz. In the PMP 450v system, a carrier refers to the center frequency of a Tx/Rx chain, which transmits and receives all modulated component carriers within its bandwidth. The maximum number of carriers is 2.

A component carrier refers to the center frequency of an OFDM symbol, and the platform supports up to 4 component carriers, though Release 24.0 enables support for only 2. Future releases enable support for all 4 component carriers. Operators do not configure the center frequency of the carrier, and it does not appear on the AP GUI. Instead, operators identify the center frequencies and bandwidths of the component carriers and determine their configuration under separate carriers or the same carrier. For example, in Release 24.0, a carrier can be configured with two component carriers, having a total width of 100 MHz, which becomes wider in a later release. An example of this configuration is shown below.

Figure 1: Example of a single carrier with two component carriers

In one carrier, one or two component carriers can be configured. If both component carriers are configured in the same carrier, they need to be within the carrier width of the carrier. Note that in Release 24.0, the bandwidth of the two component carriers needs to be the same (there is only one configuration parameter), but in a later release, this restriction is eliminated, and the component carriers support different bandwidths.

The figure below illustrates some possible configurations in Release 24.0. The two carriers can be in the same band, if the band is wide enough, or in different bands. The two component carriers can be one in each carrier, or both in the same carrier. Note that the EIRP limit applies per band. If the two component carriers are configured in the same band, the EIRP limit of 36 dBm applies to the total bandwidth across both component carriers. But if one component carrier is configured in one band and the other in another band, then the EIRP limit applies separately to each band.

To configure the two carriers in the PMP 450v AP, go to the Configuration → Radio page, in the Radio Carrier Configuration Section.

The Number of Carriers drop-down menu offers a selection of 1 or 2 carriers. If two carriers are selected, both the Carrier 1 and Carrier 2 tabs are visible; if only one carrier is selected, the Carrier 2 tab is shown as inactive.

For each carrier, first assign the band to the carrier, and then configure the transmit power and SM Receive Target Level. Once completed the Radio Carrier Configuration section, click Save. This updates the options in the next section. The next step is to configure the component carriers.

For each component carrier, first select the Carrier Assignment (Carrier 1 or Carrier 2), and then choose the center frequency of the component carrier from the drop-down menu.

As explained above, the two component carriers can be associated with the same carrier or with different carriers. Note that the options in the Frequency Carrier drop-down menu adjust according to the current selection. For example, if both component carriers are associated with the same carrier, the selection for the second component carrier ensures it stays within the 100 MHz range of the carrier. Additionally, if both carriers are associated with the same band, the radio ensures that the center frequencies of the carriers are 50 MHz apart by limiting the frequency list.

The parameters that are common to the two component carriers are configured in the next several sections, starting with the Radio Configuration section.

Once the carriers and component carriers are configured, the Radio Configuration Summary table updates with the current configuration for reference.


Any changes to the Radio Carrier Configuration or the Radio Component Carrier Configuration sections require a reboot.

AFC Support for Canada Region

The next generation of Cambium PMP products supports operation in the 6 GHz band. In the United States and Canada, this operation requires communication with an Automatic Frequency Coordination (AFC) server.

For more details, please refer AFC Operation for Cambium PMP Products document on the Cambium support site:

Support for 30 and 15 MHz channel bandwidths

Release 24.0 supports 30 and 15 MHz channel bandwidths, in addition to 40, 20, 10, and 5 MHz channel bandwidths, the PMP 450v AP enhances configuration flexibility, catering to diverse network requirements.

Backward compatibility with legacy PMP 450x SMs

Ensuring seamless integration with earlier generations of SMs, including PMP 450, 450i, and 450b models, the PMP 450v AP facilitates backward compatibility, promoting interoperability within established network infrastructures.

Problems and limitations corrected in Release 24.0

Products Affected Tracking Description
5 GHz - 450m AP CPY-18837 The issue of unexpected drops in uplink modulation performance with UL-MUMIMO traffic identified in releases 22.2 and 22.2.1 BETA was fixed in Release 24.0.
All CPY-18815 The SSL certificate date and time reset to 01/01/2020 when a power-on reset is triggered.
All SMs CPY-18745 The SNMP configuration export does not work when in NAT mode.
3G 450m/450i AP CPY-18606 User data traffic may experience higher latencies with 3G 450m/450i APs when cnMaestro was enabled.
5 GHz - 450m AP MUMIMO-3654 Uplink Interference Cancellation is supported in release 24.0. This feature was initially released in 22.2 but was not included in subsequent releases 22.1.2 and 23.0.
5 GHz - 450m AP CPYV-771 Uplink interference cancellation no longer requires a license key. This feature was initially released in 22.2, but at that time required a license key or use of the free 30-day trial. This requirement has been removed with the 24.0 release, and it is now made available for free general use for all 5 GHz 450m operators. However, operators should keep in mind that enabling this feature disables Uplink MU-MIMO scheduling. Refer to the 22.2 Release Notes for more details on this feature.

Known issues and Limitations in Release 24.0

Products Affected Tracking Description
450v AP CPY-18987 The link test shows lower throughput in the uplink when there is user data traffic in the uplink.
450v AP CPY-18799 In some instances, link test efficiencies might be too low even when the missed fragment percentage is very low.
450v AP CPY-18720 Frame utilization statistics for 2 component carrier operation need optimization. These statistics increase and decrease with traffic load and can give operators a rough idea of frame utilization, but should not be relied on for a precise measurement of utilization at this time.
450v AP CPYV-787 Auto-contention, Multicast traffic, and Proportional Scheduler (Rate Plan) features have not yet been optimized for 2 carrier configurations and are not supported on 450v APs for Release 24.0.

Additional enhancements in Release 24.0

Products Affected Tracking Description
450v AP and SM CPY-18888 Added AFC support for the Canada region.
All CPY-10284 Added support for new RADIUS Vendor ID - “Cambium” (17713).

Is this a good release for all PMP450 radios, including PMP450m 3GHz and 5GHz?

7 posts were split to a new topic: Minimum bridge table size in 24.0

We updated from R22.1.1 to R24 and we’re seeing some strange issues across our network.

We had one PMP450i 5GHz AP that would have SM’s register but the modulation on all of them would tank over a little bit of time and then the AP would dump them all. We were able to stabilize it by messing around with the channel and channel width, but there were a couple SM’s that had horrible modulation still… rolling those SM’s back to R22 fixed them. There may be a correlation between extremely high CPU utilization on these poorly performing SM’s after updating to R24.

We’ve also been seeing seemingly random drops from SM’s on a lot of AP’s. We’re going to wait 24 hours through peak time and see how things perform. If the SM registration drops continue or increase any more, we’ll need to probably roll back to R22.

In any case, I’d be extremely cautious updating to R24 and would probably only do so if there’s a specific feature or bug that you’re interested in.

There’s def something causing certain SM’s modulation to tank and then rebound on R24… rolling back to R22 resolves the issue.

It also appears as though cnMaestro can no longer graph uplink modulation on SM’s on R24.

These issues appear to effect all PMP450m and i 3GHz and 5GHz AP’s.


EDIT: the only platform safe for R24 is 450v.


TY for the updates. Seems as though I’ll be waiting a good while myself.

Thanks for the update, Eric. Did you load any of the betas we had over the past several weeks? If not that is unfortunate as that is what the betas are for, to find things like this before we do full release. We have not seen this locally as obvious as you are stating otherwise we wouldn’t have done the release. We’ll be taking a look and surely be in touch with you to collect logs and see what’s happening on your network.

We have extensively tested R24 on PMP450v with a handful of legacy SM’s and 450v SM’s. I reported strange uplink modulation issues and session registration drops with the legacy SM’s under light interference to Alan B, Rajesh, and Dhaval on April 28th with no response.

I’ve also worked with Alan B directly on uplink modulation issues tanking on R22.2, and a follow up R22.2.1 seemed to resolve these issues. From what I understand, the uplink modulation fixes were supposed to be folded into R24 release… but it appears that this has not happened.


OK thanks for the info, I’ll look into it. We did port all of the 22.x fixes to 24.0 that you were testing with 450m, but we will go back and triple check.

Thanks for the update Eric, we were about to update some legacy 450s to 24.0, glad we didnt!

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I’m well aware of who Eric is and his value to us and the community, which is why I was very surprised to see him finding these issues a day after we did the formal release. I’m not scolding anyone, just trying to figure out how we ended up seeing these kinds of issues a day after the formal release after we had many betas and delays.

We’ll find out the root cause and see how it snuck through our layers of testing and beta offerings and make corrections.

Eric, we’ve had some APs with bad upstream modulation after going to v22.0. You mentioned there was a v22.2.1 release for this? Do you know where I can find it? I’m not seeing it on the download page.
We’ve had to downgrade some APs and SMs back to v22.1.2

R22.2.1 was never made publicly available and was supposed to be folded into R24.

So is the only version that has the uplink fixes 22.1.2? Do you happen to know what earlier versions don’t have the uplink issue

I haven’t had any issues with R22.1.2, or R22.1.1.

They’re working on a follow up version for R24 now that should be out soon I’d imagine.

Any update on this issue?

Was just logging in to ask the same, we had been holding back on updates, but R24 was going to be first in a while… but ya… waiting on 24.0.1 or something i guess.

Is there any update on this issue? We have been waiting on the R24 release for the deep VC feature to allow us to use the 5ms frame period and 40MHz carriers. Provided the described issues, we will hold off until a new release is available.

Deep VC queue optimization won’t be included in R24… it’s still being worked on and is scheduled to be released in the fall.