Apple has redesigned the iPhone 4's antennas for Verizon, perhaps to foil the "death grip" problem that roiled AT&T customers last summer, an expert said today.

"They've moved things around, and my guess is that they went to a dual antenna," said Spencer Webb, an antenna engineer with nearly a dozen patents to his credit, and president of AntennaSys, a mobile device antenna design and consulting firm.

Webb was reacting to photographs that have been published on the Web that show a different configuration for the slots in the external stainless steel frame, which houses the phone's antennas.

Shortly after the introduction of the AT&T iPhone 4 last summer, customers complained that holding the device in certain ways or touching it in specific spots lowered signal strength and dropped calls.

Experts, including Webb, explained at the time that placing part of one's hand over a slot degraded performance by bridging the separate antennas, changing the length of the cellular antenna and thus its ability to receive and transmit.

The iPhone destined for Verizon has four such slots, one near the top, the other near the bottom on each side. The original iPhone 4 sported three slots, one on the top, and one low on each side.

Based on the number of slots and their symmetrical position, Webb speculated that the Verizon iPhone has two identical cellular antennas. Covering a slot on one side of the new iPhone may hamper reception, but the phone should still be able to receive and transmit properly as long as the other isn't similarly bridged by a finger or palm.

"That looks like it's a possibility," said Webb, who was taking an educated guess -- as everyone will be doing until Verizon's iPhone goes public on Feb. 10. "Apple might have done something clever here by scrambling to come up with a better solution -- two cellular antennas."

Others have also said that Verizon iPhone has multiple cellular antennas.

The technology site AnandTech, which was among the first last year to quantify the signal loss caused by a "death grip" on the iPhone 4, said that Verizon requires dual-receive antennas for devices that access its network.